Looking for Cheap Textbooks - Or, Cheap Books in General?

As an 'amatuer' level genealogist, I understand how many books, software, memberships, etc can be thrown at you. While some are necessary, some are not. And SOME are just downright expensive, whether necessary or not. Here is a great place to locate cheap textbooks (every now and again, my research calls on me to study something I've never had the desire to, to become more acquainted with an individual or their history): www.textbooks.com

Need to just find books in general - not necessarily New, but "gently" Used or just 'Used' - with an equally acceptable price? Try my company, Textbookcenter on Barnes and Noble's Used/Out of Print section - all orders over $25 receive a free upgrade to UPS Ground delivery! For example, try this link to a common Biology book, to see more reviews about Textbookcenter, the #1 Used and Out of Print third party seller on BN.Com:
http://search.barnesandnoble.com/used/productMatches.asp?PEAN=97808...

Lastly - just looking for a book, for an extremely cheap price - that you know you wouldn't find anywhere other than a library book sale for the price you want it? Check Out One Planet Books - They sell on Amazon, as well as their main website! Google it!