You can probably pick some up off the ground on the way in to the stadium.
Srsly, I've found that buying tix from people at the game is much easier at the bigger games than the ULM's and Western Kentucky's. It seems people that come to the weak OOC games aren't coming to waste time trying to make buck off tix to a bad game. They're coming to tailgate and watch a little AU foosball. I remember not having tix to the epic Furman clash in 09'. The game had kicked off by the time I finally decided to pony up face value at the ticket booth.