I wasn't familiar with this site until just now. I'll have to add this to my rotation of used book searching.

When I buy a book, I usually check Ebay, Thriftbooks, and Amazon (new and used) and do a comparison. Some books just can't be found for much cheaper than their brand new price. Most of the books I buy and read are software related, and some of those just hold their value. I'm pleasantly surprised by Better World Books though, this is the cheapest copy of GoF I've seen at $15 for the standard hard cover, that's a steal! Even the used copies I find are within $5ish of a new print (just about $40).

It's hard to find good software books at a library, usually you'll have something like "XHTML for Dummies" and that's it. If anyone has other suggestions for good places/ways to get technical books, I'm all ears.