Well that's a very broad question you've got there, so I'll try to give a little summary. For the most part in medieval Europe the shoes were stitched from leather and had quite a lot of variation - from low shoes to high boots (depending on the period) - here is an example of a modern reconstruction of a pair.

The trend was for earlier shoes to have rounder front like in the pic above, while in the XIV and XV-th centuries the fashion shifted towards shoes with a distinct sharp "tip" - http://www.parttimepolymath.net/Images/shoe_men_14th.jpg

During the XVI-th century however shoes with flat fronts were back in fashion.

At least in Western and Central Europe shoes would often be worn with wooden pattens. From my experience these are quite uncomfortable, and I would argue that they were reserved for bad weather, however I cannot support that with sources. In South-Eastern Europe and the Byzantine Empire I am not aware of any pattens. But on the other hand there are quite a few murals and frescoes that show sandals and a sandal-type shoe particular to the region ( that has evolved a bit since then and is a common part of folk costumes - http://bnr.bg/sites/hristobotev/shows/society/nashiat-den/society/PublishingImages/260/11-12-07-03147_1.jpg

Now the clothes. I think that during the time of William the conqueror trousers were not really popular. What people wore was this from England to the Byzantine Empire and this was the thing up until mid-XV-th century. During that time each of the "socks" basically grew longer, covered more, until at the end merged into this: http://www.medievaldesign.com/restricted/immagini/1grande_9726.jpg In fact this is the predecessor of modern trousers, while the ones that we inherited from the Romans and Gauls during the medieval period became the white underwear you could see on the pictures above, and ultimately what today is our underwear. Also women's hosen were a bit shorter, although men also wore the short version. THat thing around the knee that holds the hose up is called a garter and men wore them too - it is really helpful in preventing the hosen from sagging.

In the Russian steppes I think they had schalwars from pretty early on.

While we're on the topic of underwear - shirt was commonly worn under all layers of clothes. Early on it was longer - mid-tigh or to the knees (probably even longer for women). - Here is the pattern of one from Egypt(although pretty similar to what was worn all over the pace. And here is a reconstruction of the same garment on the [left] (http://medievalisticals.files.wordpress.com/2012/01/267268_10150266577173557_545253556_7699673_8196650_n1.jpg) The guy on the right represents an XI-XIIth century russian, the guy on the left a XII-th century bulgarian/byzantine whatever peasant.

Later on mens shirts became shorter, as the fashion moved towards shorter top garments. Also at least from the XV-th century on we have evidence of "bras" - which were something like a mix between a tank-top and a bra.

Top garments - early on - tunics - here is an original from c. 1100 and on top of the tunic a thicker tunic, or a bunch of different surcoats. Here is a womans surcoat.

Sometime around late XIII-early XIV-th century tunics became more tight-fitted, and started becoming shorter, until it resembled something like this. Here you could also see how dresses also became tighter and started showing some cleavage.

The mid XIV-th century also gave rise to a very peculiar garment - the doublet. It's origins are kind of mysterious, and the chief hypothesis is that it developed from the padded garment one puts under their armour. In fact all later armour is basically fastened to the doublet. Here is a picture where you can see where the pauldrons are fastened.

However apart from military garment, the doublet was also civilian one. Initially it was worn under the cotehardie - the tighter shorter tunic of the mid XIV-th century, but later was used on it's own. Initially it was quite long reaching up to mid-tigh, but in the XV-th century it gradually got shorter, coming up to this thingy in the XVI-th century

Back to dresses (yaay!) There was still some variation, but they kept the tight upper body from the XIV-th century- here is a XV-th century pic. ANd another one. The female version of the cotehardie would follow closely the lines of the underdress and would look stunning for that ball, especially when the colors of the underdress complement these of the overdress. Also check this out from the early XV-th century

Over-garments. Early in the XIV-th century and in the late XIIIth century your friend against the cold weather would be the gardecorps goes for men and women. Richer folks would get some cool overgarments like the blue houppelande of the guy above.

In the east of Europe things were a bit different - you don't get doublets, but tunics remain popular. And of course various forms of the kaftan - which ranged from short mid-thigh ones to long and really fancy ones. Here is a reconstruction of a fancier one Women's dresses also tended to be not that fitted. Or at least that's what the Orthodox paintings show. However, there appear to be quite fancy and richly decorated dresses - [Here] (http://static.panoramio.com/photos/large/19615843.jpg) is a mid-th century mural of some fancy guys. Note that the guy here shows some Ottoman influence - the wide sash, as the place was under an Ottoman rule at that time.

I'm not touching the headwear, cloaks, accessories, belts and stuff. I'll leave these to yourself.

edit: A bit more on how we know all this stuff (as /u/telkanuru suggested). As can be seen most pictures there are of modern reconstructions and I've tried to select the best ones (finding properly reconstructed doublets is kind of hard). Usually these are based on existing originals ( this is a great site that lists a large part of the surviving medieval garments) and images of the period (here is my favourite for images from different manuscripts), the Web gallery of art is another place with art from many different periods. The good thing for Western and Central Europe is that there are tons and tons of sources .

The same is not the case for the late Byzantine Empire and the Balkans, where there are few sources, often unclear, and are nearly no surviving garments and there aren't many people that do extensive research on the topic, and most information is not available in English. The last image is taken from the mid XV-th century Kremikovtsy monastery and the reconstruction of the blue Kaftan is based on the XIVth century church in Kalotina, near Sofia, Bulgaria. The yellow kaftan I believe is based on this image from the Meneologium of Basil II, but I don't know the guy and I can't be sure.

The original doublet up there is one of the best preserved examples - the doublet of Charles du Blois. Here is more on doublets by Tasha Kelly - probably the best expert on this type of garment in the world (although she is not an academic, she recently published a paper on the specific example mentioned above).

Since you mentioned you had read into Byzantine history, I can give you a little insight into that area of medieval society. The historian Procopius touches briefly upon what some members of the racing factions (comparable in some regards to modern football hooligans) began wearing under the reign of Emperor Justinian. He recounts,

"Next they decided to wear the purple stripe on their togas, and swaggered about in a dress indicating a rank above their station... The sleeves of their tunics were cut tight about the wrists, while from there to the shoulders they were of an ineffable fullness; thus, whenever they moved their hands, as when applauding at the theater or encouraging a driver in the hippodrome, these immense sleeves fluttered conspicuously, displaying to the simple public what beautiful and well-developed physiques were these that required such large garments to cover them."

So not all clothes in medieval society, at least within the Byzantine Empire, were purely functional. Some people were pretty fashion conscious and just wanted to show off! Granted, its doubtful that these same people were working laborious jobs (although Procopius mentions them being street thugs) which would have required more practical garments.

Source: Procopius. Secret History. Translated by Richard Atwater. Forward by Arthur Boak. University of Michigan Press, 1976.

This is a really, really broad topic to tackle. You are, after all, asking about a period of almost 400 years. I hope my fellow readers (and moderators) will forgive me for any minor inaccuracies or simplifications.

The turnshoe was pretty universal throughout most of the medieval period. This could range from a low, slipper like shoe, to an ankle boot. Knee-high riding boots seem to have developed quite late in the period.

http://www.deviantart.com/art/Finished-Turn-Shoes-143609645

For clothing, the tunic or kirtle was the dominant garment for men or women up until the Late Middle Ages. This would be a long (thigh to ankle-length) unstructured garment, most commonly of wool but occasionally of linen and, rarer still, silk. A longer, more decorated tunic may have been worn as an outer garment, variously called a supertunic or overtunic. Cloaks were very common, being generally rectangular or semicircular. Trousers were worn with them initially, but this gives way by the High Middle Ages to woolen or linen hose, secured to the braies (undershorts) by ties. The Normans at least seem to have covered the lower legs with strips of overlapped fabric as an added protection.

I can't speak for the Late Middle Ages with real certainty.

You're asking for a hefty bit of information here, so I'm going to break this down on a very basic level, period by period. First, some basics: Cotton was not a widely-used fabric in medieval Europe. The standard fabrics of the time were linen, wool, and silk (for the wealthy) in all sorts of weaves and in various colors. Dharma Trading has a good natural-dye color chart to give you an example of the colors. There were also always undergarments of some sort. They weren't always structured brassieres, but there were undershirts and underpants beneath the outer layer of clothing to preserve that outer garment. And, yes, fashion evolved. In the early medieval period, a sweeping generalization can be made that most European medieval clothing was relatively the same. By the middle of the medieval period and most definitely by the end, different regions had developed their own styles. 9th century Norse and Saxon clothing were very comparable; late 15th century Italian and northern German were very, very different.

Secondly, yes, they wore trousers back then. Mankind have been wearing trousers for a long time. While not a very historically accurate show, Vikings did get at least one thing right: 9th-10th century Norsemen did wear trousers. In fact, here's a Scythian archer wearing trousers from about 500 BC.

The first period we'll cover is the early 11th Century, the time of William the Conqueror. William's exploits were recorded on the Bayeux tapestry, which is a solid visual aid for clothing of the period. Average's men's wear consisted of layers of knee-length tunics, slim-fitting trousers, legwraps, circle or square cloaks, hoods or knit caps, wool socks, and leather boots. Women wore long dresses with a chemise underneath, along with hoods or veils, circle or square cloaks, wool socks, and leather shoes.

By the end of the 12th Century, the time of Richard the Lionheart, we're moving toward a more recognizable period of medieval fashion. Married ladies wearing tight-sleeved or angel-sleeved dresses and long, wispy veils and men wearing longer tunics, colored hose, and close-fitting caps. That's what we're looking at here.

The late 14th and early 15th centuries are the times of Jeanne d'Arc, Henry V of England, and entering into the most popular "Knights and Maidens" looks. Everyone wore the cotehardie; the men wore it much shorter, the women wore it long, and it typically buttoned or laced up the front. Sleeves could be loose tight with lots of buttons or loose with a fitted cuff or just loose angel/bell sleeves, belts were popular, and hoods had grown liripipes (or long tails) in the back. Shoes were made of leather and had developed longer, pointed toes that were often stuffed to keep the point rigid. Women's headdresses were evolving to new heights (think the conical hat with the veil - this is one style of hennin that became popular during the 1430s). The later 15th century and 16th century was a time of extreme change in fashion as pairs of bodies, corsets, codpieces, uncovered women's hairstyles (scandalous!), and more were introduced, so I won't go much into it here.

The Web Gallery of Art has been my best tool so far, beyond extant garments. Looking up scans of medieval manuscripts (like the Digital Manuscripts by Harvard)will be your best tool for early medieval sources. Unfortunately, most of my sources are at home, so I can post some of my hoard of links and photos after I'm off work.

Scandinavia was probably far fram behind France and the Italian peninsula when it came to fashion in the middle ages, but I can recommend you or anyone else interested in medival clothing to visit Varberg Fortress in southern Sweden. This is where the remains of the medieval "Bocksten bog man", and his clothes, are stored and on display. So what's so special about this man? Short answer: his clothings are largely intact, making it the only fully preserved men's dress from the middle ages. I'm afraid I can't provide you a non-swedish source, but here's the museum's own web page:

http://www.hkm.varberg.se/bockstensmannen/kladerna/

I recently finished "Jarlens sekel - en berättelse om 1200-talets Sverige" ("The Earl's / Jarl's Century - A Story of 13th Century Sweden"), by Professor Dick Harrison, which made me aware of the difficulties medieval historians face when it comes to finding sources. Medieval historians depend quite a lot on archeological findings, since (profane) written sources are rather uncommon, and if they do exist, they rarely reveal much about ordinary people's lives, let alone their clothings. There is only one problem: archeologists don't dig up medival textiles because they have since long disappeard, unlike i.e. bones and metal weapons.

The Bocksten man, however, is a "bog body": his murderers buried him in a bog, unintentionally preserving his clothes and some of his bodily remains. Quite a few bog bodies have been found in northern Europe, they are especially common in Denmark and northern Germany. These bog bodies are of course excellent sources for archeologists and historians, i.e. the "Tollund man", whose well-preseved remains and clothes have been dated back to the iron age.

So how representative is the Bocksten man? Would an ordinary scandinavian farmer have worn similar clothes back in the middle ages? First of all, it must be pointed out that scientists have been unable to date his remains to a specific century. A recent carbon 14-analysis places him somewhere between 1270 - 1320 or 1350 - 1390. Scientists believe that he died somewhere between 1370 - 1390, but better safe than sorry, and although Scandinavia was a poor and backward region of Europe, one have to assume that the everyday fashion might have changed somewhat between 1270 - 1390. Furthermore, it's plausible that the dress isn't representative at all for an ordinary 13th century scandinavian, let alone for a contemporary man living in France or England. Most archeologists and historians agree that although it's impossible to confirm his identity or occupation, his gugel (the hood) was normally worn by wealthy men or by men of the church. Nevertheless, he remains a very interesting example of medieval clothing.

Sources: Harrison, Dick, 2002: "Jarlens sekel - en historia om 1200-talets Sverige", Ordfront förlag, Lund. Hallands kulturhistoriska museum (Varberg Fortess).