There are some really good old army tents here... I would love to get the temper tent, which has an expandable frame, is 18' wide, 16' TO 64' long, and made of light weight vinyl. It costs about $940.00 for starters, however. The cool thing about this tent is that it's modular... you can get a bunch of them and hook them together over time.
On the other hand, there's always your standard army general purpose tent... heavy as hell, but about half the price. Probably takes longer to set up though.
Maybe I should see if I can find these for less. Hrm.