1-Rare books: In this website you will find a collection of very rare books photographed at very high resolution.
2-Books mirror: Here you can find a list of very important books.
3-authorama: Here is another great source of books.
4-50 Amazing Books: and here is a list of books you MUST read!
5-librivox: Listen and download books for free (you can also record books and send them)
6-Banned books: Here you can find banned books.
8-bartleby: here you can search books easily.
9-planet book: a blog full of amazing books.
10-calssic reader: free classic books.