Wolfram alpha is also fantastic for math. Mailinator is definitely the best throwaway mail account site. You can put any firstname.lastname@example.org, then without even going to the mailinator site, sign up. If you need to verify, you can go to the site.
Compare College Textbooks | Used Textbooks | SlugBooks I just barely went here, and it is awesome. I got 4 of my textbooks for $30 all together, when one was that much at the SUU bookstore. I'm doing a happy dance.