for ebooks, maybe you'll try electronic librarries such as Questia..
or these:
Internet Public Library: Reference
http://www.ipl.org/div/subject/browse/ref00.00.00
LibrarySpot.com
http://www.libraryspot.com/
.
Librarians' Index to the Internet
http://lii.org/
Also, do not forget about Gutenberg Project:
http://www.gutenberg.org/
This source is also cool:
http://www.infomotions.com/mylibrary/
Cheers!