http://lab.lpicn.org/pub/books/
http://www.giuciao.com/
http://www.dotnetspider.com/books/
http://www.intelligentedu.com/free_computer_books.html
http://www.e-isn.com/home/indexhome.php
http://www.gayanb.com/
http://www.dhruvaraj.com/
http://etext.library.adelaide.edu.au/
http://www.gutenberg.org/wiki/Main_Page