Oh, and for books, I tend to use half.com, and save a ton.
If you want to risk it, I know a couple of people who ordered their books on half or whatever the second they found out their section. Until they arrived, they bought books from the bookstore, but then never highlighted or wrote in them, and returned them w/in the return period. It's kind of underhanded, but if you're poor, you have to do what you have to do, I suppose. It probably doesn't work with books that are shrinkwrapped, which you get occasionally.