Skalla Geirmundr inquires about useful medieval cooking or food sites, particularly regarding food cooked in the field or on campaign. Most medieval cookbooks, of course, refer to dishes for aristocrats, but a good start would be a SCA publication called Traveling Dysshes, which discusses medieval cooking from that very perspective.
Some other favorite sites:
Medieval and Renaissance Food Hompage
To tell the truth, I've never explored the web for medieval cooking sites very carefully. I've got a fairly substantial collection of cookbooks and books on medieval cooking in general, and haven't come anywhere close to exhausting the possibilities there.