#1 - How big was a typical army?
Depends on what you mean by army. Throughout the medieval period there are many different types of armed forced operating in Eurasia with numerous motivation, organizations, and support structures. Even if you are limiting things to strictly controlled and supported permanent national forces with a political goal the numbers vary greatly. The overall range for these forces would be between 1,000 or less for an elite king's guard to the close to 200,000 permanent Turkish Troops maintained by the Ruler of Samarkand. That particular ruler had a lot of trade and political centralization and was thus free of some of the population constraints mentioned earlier. The Mongols took him out. I do not know how large their total numbers were but they organized themselves into 10,000 man divisions.
#2 - What troops were in it and what were their numbers?
Again wildly various, however, most of the more famous armies of the period relied very heavily on mounted troops. Competent Infantry Forces are pretty much limited to conflicts in Iberia, the Saxons, early Franks, Late Romans, Vikings, Scotsmen, Swiss, Byzantines, and late Germans. The game Medieval Total War gives you a good idea of the variety of troops involved though it does seem to me to overemphasize infantry.
#3 - Any sort of 'Special Ops' units?
Yes. There were many elite units and much of the period was characterized nearly entirely by small scale conflicts involving only these troops and then sieges involving larger forces of cheaper units. William the Conqueror, for instance, spent 40 years of rule in ceaseless conflict, but only fought in two pitched battles. Eleanor of Aquitane immobilized all of France through the skills of William Marshall and a small group of knights in the conflicts following the death of Henry II. El Cid only commanded an army at the end of his career, and most of his more celbrated victories were accomplished by a small band of elite fighters. Some theorists argue that current reliance on special forces is a return to the most basic pattern of warfare.
#4 - What type of equipment would ordinary infantry have?
Wildly varying, there are a few basic patterns for horseman but infantry vary a great deal. Infantry are going to be better equipped in the dark ages, worse in the high middle ages, and better again at the end. Peasant levies were often abysmally equipped, but many knights brought with them retinues of well equipped men-at-arms who were more than able to serve as able infantrymen and archers.
#5 - In a generic fantasy setting, how would magic and healing abilities play into the army?
I've seen a lot of differnt arguments for this. Personally I feel that the effect depends just as much on the type of militaries that you are playing with as on the level of magic. We tend to think in terms of large national armies, and most of the arguments for magics tremendous effect seem to focus on that aspect. I have seen very few arguments as to how it would affect the patterns of warfare most common to the period. Personally, I believe that DnD is balanced very well for that pattern and so magic tends to play out 'naturally' in that arena.
#6 - What type of food did the troops eat? Just ordinary tail rations or were they fed with cooked food gathered by hunters?
Grain would be the most common form of ration and fodder. Lots of scrounging did occur but the best armies had particular supply systems. The Feudal system commonly expects people to show up with food to support them for forty days, the length of their obligation, beyond which time whoever is employing them is expected to provide the men with food or the men are pretty much free to abandon their commander, something that happened fairly frequently. The Vikings had elaborate systems for calculating and distributing supply without the aid of mathematical notation. Mongols carried herds with them and every soldier was equipped with yogurt culture. Most armies who weren't willing to loot, it really slows down your marching, would organize markets in which the locals would sell the normally comparatively wealthy soldier all they needed.
#7 - Did I ask to many questions?

Never!!!!
Anyone have any sites for this kind of info? Or book suggestions, etc?
There previous suggestions are very good. There are some new fairly radical theories on the practice of medieval warfare, but they are likely to be in high academic language at this point, and probably in German. I can make a few recommendations for primary sources:
1.) There are several Byzantine books on warfare and tactics from the period. I do not know how difficult they are to find. They are much more specfic than Vegetius, who was the most frequently read theorist in Western Europe, and are give explicit details on the armament, tactics, politics, organization, and logistics of armies of the period as well as information on how to exploit them.
2.) The Alexiad of Anna Comnena, the Lives of Charlemagne by Einhard and Notker the Stammerer, and the Life of St. Louis by John of Joinville are my favorite military books of the period. The Alexiad actually serves as the basis for much of Dune.
3.) The literature of the period is filled with accounts of warfare that are fairly accurate, they just don't tend to reflect the large scale warfare we are intrested in. Malory of Morte D'Arthur, for instance, was a veteran of the War of the Roses and the picture he paints of knights running around kidnapping people and fighting in small battles does have literary and mythical levels, but it is also reflective of the world he knew.
The best army at war book from the pre-modern period is, in mine and others opinion, The March Up Country by Xenophon. It's from a much much earlier time period, but it is still very informative about many of the basic issues and tactical situations a pre-modern army that wasn't Roman would face. Said to have inspired Alexander the Great.
All of the books I've listed titles for can be found in Penguin editions.