The textbook industry can be pretty cutthroat when it comes to college students. They know that we've got to have the books to pass the class, and they charge a pretty penny for it, then come out with a new edition for the next term so the bookstore won't do buybacks. Legally, extra materials must come unbundled now, but a student could easily spend $500 in a term on books. It's shameless, really, but there are ways to avoid spending quite so many hundreds of dollars.
1. Know what you really need. If you think you can get away with it, put off buying books until you get your syllabi for your classes and se what you'll actually be reading. There's not even any harm in emailing your professor beforehand and asking him or her for a syllabus. If you're a third or fourth year English major, you might already have some of the material already, if you saved your Norton Anthologies. There's no point in buying a new book to read a small poem or play you've already got.
2. Use the internet. Materials for which the copyright has expired are usually available for free online. Try Project Gutenburg or Bartleby. Don't buy a glossy copy of Shakespeare's sonnets. Find the ones you need online and print them off for class. Entire novels are now in the public domain and can be downloaded for free for ereaders or to your computer. Historical texts are also out there.
3. Visit your local library. The campus library is nice, and may be the only place you'll find a particular textbook, but it's saturated with students all after the same materials. English and history majors should have an easy time finding novels and poetry collections at the public library. Library cards (and books, and CDs and movies) are free to those living inside the city limits. Just make sure you've got a hold on the book about a week before you have to read it for class so you're not scooped by someone else. In which case, quickly head to the campus library and order it through Summit. And do return on time; overdue fines are not compatible with the skint student lifestyle.
4. Take a class with a friend and share the cost (and the book). This works best if you live with the friend, because you don't want to be chasing someone through Facebook 2 hours before your test. It also gives you a good excuse to study with said friend and quiz each other.
5. Buy used whenever possible. If your professor hasn't made a deal with the devil/publishing company, they'll use a book that has been in print for a while. You've got several options for used books at UO: the UO bookstore, which supposedly gives 32% off used books to students; Smith Famly Bookstore, a locally owned shop with a location near campus with many of the textbooks available, and a general bookstore across from the downtown post office; and online sites like Amazon.com, Half.com, and Barnesandnoble.com. Keep in mind that extra shipping charges apply, which may trumps any savings from buying online. When you buy used from Amazon.com, remember that shipping applies to each book, as they will come from different dealers.
6. If you have to buy new and the price is the same, buy from the UO bookstore during the rush. There's always the chance that you'll win the free book lottery, but this could end up being an expensive last resort too.
Near the end of term, shop around online and find the highest price for the textbook you've got. Buybacks at the UO and Smith Family bookstores are often a ripoff for the price you paid. You might actually make a few bucks on a book or two if you do your online research. From what I can tell just by looking online, the best option would be to buy the book on Amazon.com or the UO Bookstore, and sell through through Barnesandnoble.com or Half.com.