(Yes I have googled it and nothing came up dear mods)
Part 1
Uniforms were usually manufactured by the men within a regiment. I'll talk mainly about the French system but other countries would be similar.
Each regiment would appoint a Clothing Officer (capitaine d'habillement) who would remain at the regimental depot and supervise the regimental craftsmen and was responsible for procuring more specialised items from external contractors. Prior to 1808 he was one of the company captains who were rotated on an annual basis; this was changed to one of the commanders of the 4 depot companies. Finally in 1811 it was changed to a specialised position without command of a company. He would have two assistants - one responsible for uniform manufacturing and distribution and the other for arms and equipment. This was a highly responsible position, he would control considerable sums of money and the power to choose external suppliers; there would be plentiful opportunities for corruption for the dishonest officer with unfortunate effects for the regiment - Napoleon wrote a scathing missive to Minister of Administration of War in September 1811 on the condition of the newly formed Regiment d'Illyrie: the jackets were too short and not properly lined, buttonholes were merely cut out and not lined, shirts were too short, shoes didn't fit, haversacks were poor quality and too small, shoddy cloth etc - the Emperor wanted those responsible to be found and punished. One oddity was that the capitaines d'habillement of the Old Guard Grenadier and Chasseur regiments were also responsible for the more junior regiments in the Middle and Young Guards - apparently they were somewhat neglected compared to their more illustrious seniors.
There would be four master craftsmen (maître ouvriers) underneath the capitaine d'habillement - a tailor (ranking as a sergeant), an armourer, a shoemaker and a gaiter-maker (all ranking as corporals) who would remain at the depot as non-combatants. Two of the regimental children (enfants de troupe) would serve as apprentices and appropriately skilled soldiers would be seconded to assist. New recruits would visit the tailor to be measured for their uniform and a uniform would then be manufactured. Once complete, the man would try on his uniform in front of his officers - any irregularities were to be made good at the tailors expense. Uniforms weren't made to measure, each piece would come in regulation pattern and size and would be adjusted to fit. Each company would also have at least one company tailor paid for by the company fund raised from the sale of the effects of dead men and deserters and pay stoppages for men on leave. The tailor (and the company barber) would be excused from cooking and fatigue duties and in garrison they were able to go into town to practice their trade; in exchange his pay would be deducted for food and linen and to compensate another man to care for his gear.
Uniforms would be paid for out of a regimental clothing fund (masse d’habillement) which was set at 48 francs 29 centimes per annum for the line infantry, a hussar by comparison was allocated 80 francs 41 centimes. The fund would also recover repairs and replacements not due to negligence on the part of the owner. The capitaine d'habillement could receive cloth from the army administrative service (service d'habillement), where the cost would be claimed as expenditure against the uniform fund; alternatively units could buy cloth locally - in Spain for instance, brown cloth was plentiful and inexpensive and brown trousers were endemic to unit stationed there, breeches usually being the first items to wear out and resupply from France being almost impossible. Russia had two state owned factories to produce cloth for the army at Yekaterinoslavl and Pavlovsk staffed by Invalid (wounded veteran) Companies. Captured or requisitioned materials could also be used during lulls in campaign to manufacture and repair uniforms in the field. Buying cloth and manufacturing uniforms within the regiment was usually cheaper, provided better quality results and helped to keep the men busy in garrison. Before the unified dress regulations created by Bardin in 1812 each regimental tailor would create a sample uniform and present it to an inspector at review for approval based on whatever directives or organisational decrees were then in force - this could lead to significant variances based on the financial state of the unit, the quality of local cloth (even the properties of local water could change the colour of cloth when it was dyed) and the preferences of the regimental colonel; indeed it seems that practically every regiment had different pattern of shako plate. Colonels with extravagant uniform tastes were known to use funds reserved for food and fuel to outfit their regiments - much to the Emperor's displeasure; other regiments were luckier - the Colonel of the 20th Chasseurs was a big gambler, when his luck was with him he would buy the regiment new gloves or plumes. Men with tailoring experience were surprisingly common in armies of the era, one Prussian regiment did a survey in 1777 and found that of the 327 professionals listed in the regiment there were 67 tailors, 61 shoemakers and 2 leather workers; soldiers wives who lived near the depot would also assist with the sewing. Officers were expected to pay for their own uniforms; though newly promoted sous-lieutenants received their first uniform for free from the uniform fund, provided they had served for 5 years. Other officers would pay private tailors or could have them made up by the regimental tailor - they would be assured of getting good workmanship and regulation style and could get credit if they were short of cash. When units were in the field, uniforms would be produced at the depot and then sent forward alongside groups of newly trained replacements being sent forward.