Facebook?
One of the better ideas I had in college was to keep my receipts, get buy-back quotes from the book stores, know the used worth, and find a cash middle-ground with other students so everyone wins.
Even here may be a good place to ask--Lots of college students and recent grads on here. I know I still have a bunch of books sitting in boxes collecting dust, courtesy of Rutgers and my own Senioritis.
