I'm surprised how difficult it is to find any information on the dates of extant copies for any roman writing. The conversation seems to be dominated by the dates of extant biblical sources. Obviously we have a huge volume of work from Cicero, but who copied them, how old are they, and where are they today? Is there a table that shows the extant date and location for each work like what we can easily find of the books of the Bible?
Those dates are relatively easy to find, as are their current whereabouts, if you know where to look. The 'who copied them' is a bit harder.
Pretty much all prominent Latin (and classical Greek) works that have been found, were published in critical editions. But, as you've said, we have a huge volume of work from Cicero. Several manuscripts contain the same texts. And I can assure you, when copying a text, mistakes slip in. So, how do we know what the 'real' text is? For that, we need to collate the manuscripts. Collation is nothing more than comparing the texts from the different manuscripts and, whenever you find differences, you make an educated guess as to what would have been the originals words of Cicero. The result is the critical text, printed in a critical edition.^(On a side note, I personally find collating a tedious and mindnumbing job, but I had a friend who absolutely loved it, because he could go down to the library and spend hours perusing old manuscripts and comparing word after word, letter after letter. God bless the people who that kind of patience!)
Anyhow, before it gets to anecdotic and this reply gets removed, on to your question. After you've collated these texts, you want to show the readers what you've done: they might have other ideas on certain decisions you made. That's why, at the bottom of the text, you mention all differences you've omitted from the text, in the so-called critical apparatus. (If I can, I will add a picture later to illustrate ). It also means people need to know what manuscripts you've used. So, in every scientific edition, you will find a list of manuscripts used.
Now, there are three main series of critical editions, the Budé-series (French), the Loeb-series (English) and the Teubner-series (German, but without translation), and I happen to have works of Cicero from both the Budé- and the Loeb-series.
So, to illustrate, here's such a list taken from the Budé-edition of Cicero's Pro Murena, edited by a certain A. Boulanger (again, will post images later if possible):
What does this mean?
- The first letter is the siglum. It's kind of an abbreviation of the name of the manuscript, used to denote the manuscript in the rest of the book.
- after the equal-sign, you find the name of the manuscript. The abbreviation 'cod.' stands for codex, or 'book' in the sense of a material object (not 'book' as in a coherent text). The second part stands for the place/library it was found, and the number is the catalogue number. So cod. Laurentianus XLVIII is the 48th book in the catalogue of the Laurentian library (in Florence, Italy).
- After that, you might see 'scriptus', which means 'written'. If it just says 'anno XXXX', the manuscript was written in that year. For this edition, Boulanger was lucky and managed to find the exact year the manuscript was written for two codices. Often, it was not as clear when it was written and you just see 'saec. XIV' or something like that. (It means '14th century'). Generally, you can assume that the editor was as specific as he could. Nevertheless, these days the internet might help you find a more specific date, (a luxury these editors didn't have!).
- In one case, Boulanger even managed to find the copyist's name, denoted by 'a I. Arrentino' (which just means 'by I. Arrentinus'). Again, you can be certain the editor did his best to find the name of the copyist. This is a lot harder though, and I will explain why.
With these manuscripts, it wasn't usual for the copyist to sign his name or the date. Sometimes we get lucky and there are clues or it is said outright, but in a lot of cases, we have to use our detective skills. For dates, it's relatively easy though quite unprecise. The 'font' of these manuscripts changed over time, as did some of the writing implements (parchment and ink used, for instance) and the style of the illustrations. That helps us narrow down the date of writing to about a century, sometimes even half a century.
The question who wrote it is even harder to answer, because we need to know not just when the manuscript was written, but also where. And even then, most scriptoria (the official name for places where manuscripts were systematically copied) employed multiple copyists, who sometimes all worked on the same manuscript.
As for the oldest manuscript containing work of Cicero: I haven't a clue. The oldest manuscripts I can find in my critical editions are from the 9th century, (one was in Holkham Hall library in Norfolk, but nowadays found in the Bodleian library in Oxford, the other is in the Harleian Library, which is part of the British Library in London). It also doesn't say who copied them.
A definitive list of manuscripts you might find in an Opera Omnia (= complete collection)-edition, although I couldn't find a reliable one that quickly.
Everything I've written above (except for the details) goes for every well-known Latin and Classical Greek writer. Unfortunately, for a lot of lesser known writers, especially medieval ones, there are no critical editions (yet).