Free Multilingual e-Books

http://www.e-book.com.au/morefreebooks/freemultilingualbooks.htm
http://multilingualbooks.com/ebooks.html

10 Web Book Searching Tips

http://www.bookride.com/2010/05/10-web-book-searching-tips.html

Allows searching by plot elements, theme, characters, and setting.

http://www.allreaders.com/booksearcha.asp?subjectid=4
http://www.arbookfind.com/default.aspx

Searchebooks

http://www.searchebooks.com/

Compare prices of 150 million books for sale

http://www.bookfinder.com/

How To Find Out-of-Print Books / Site

http://marylaine.com/bookbyte/getbooks.html
http://used.addall.com/

AddALL Used and Out of Print book search

http://used.addall.com/

Book Searching: Full Text Book Search Engines

http://www.searchengineshowdown.com/booksearch/

Items in Library Near You

http://www.worldcat.org/