One of the most annoying expenses for college students can be the cost of college texbooks. First of all, why do college textbooks cost so much? And second, most of the time, the the textbooks aren't ones that you really want to keep, which just adds insult to injury.

Enter the world of cheap and used college textbooks.

Luckily there are many options nowadays for students to both get their textbooks at a discount and to sell back the textbooks they don't want.

Like in any marketplace, supply & demand plays an important role in determining the market price of college textbooks. And luckily, much of the time supply outstrips demand which means that you can get some really great deals.

Now, the "scam" used to be that college bookstores wouldn't sell older editions of a textbook or even used editions of a textbook. My college was nice enough to actually sell used editions, although I can't recall if they ever sold older editions.

Now there are places like BookByte.com and PhatCampus.com where you can buy college textbooks at a hefty discount.

If you're worried that the new edition is significantly different than the older edition then you can do a couple things.

First, you could check a place like IChapters.com where you can download a digital copy of textbooks for half off. You can also download individual chapters there which sometimes can work out to be much cheaper if you only need certain chapters of a textbook.

Also, if you want to make sure the editions of a textbook haven't changed significantly you can check the table of contents of each one. Often you can do this at Amazon.com or sometimes even at your college librrary or even your college library's website.

Of course when most people think of buying used college textbooks, probably the first places that come to mind are eBay.com and Half.com. And those are definitely places you want to check in addition to Amazon.com and the other sites I've already mentioned.

But don't forget to check with your classmates as well. Sometimes both you and your classmates can get a better deal by dealing directly with each other rather than going through a middleman.

Of course don't forget the flipside of all these transactions. You can almost always sell to the companies that you buy used college textbooks from. For example, BookBytes.com, WeBuyTextBooks.com, and PhatCampus will buy textbooks if you have the ones they need at the time.