Although being familiar with the available technology at our fingertips has become increasingly important over the last few decades, I figure that the foundation of any library program still centers around books and the love of reading. It does for me, anyway. With that premise in mind, I chose to explore the award winner Biblio.com (2nd Place, Category: Books). A user can find really rare material if he or she is looking for it. I don't usually need to find rare material, but over the last ten years or so I have made an effort to replace every paperback in my collection with a hardback version. I know it can be viewed as a waste of money and/or a little neurotic, but I just prefer hardbacks over paperbacks. They hold up better and, with proper care, can stick around for more than a few generations.
Biblio.com helps with my hardback vs. paperback dilemma. I searched for a hardback version of George Orwell's Homage to Catalonia - I've been looking for one for a while - and found a few editions to that I can choose from. I'll probably purchase a copy after completing this post, actually. I like that a user can set very specific parameters (ex: first edition, dust jacket or no dust jacket, stores in the U.S. or both the U.S. and abroad, price range, etc.) so he or she doesn't waste a lot of time looking through irrelevant material. This website looks to be very useful and is a lot more thorough than more general purchasing sites like Amazon.com, Buy.com, or even BarnesandNoble.com or Borders.com.
Here is a link if you are interested: http://www.biblio.com/