E-Books
http://www.gutenberg.org/wiki/Main_Page
Project Gutenberg offers over 45,000 free ebooks
http://www.textbooksfree.org/
This site provides free text books and course notes, free courses, information on free internet libraries and much more
http://www.readprint.com/
Read Print.com is a free online library. The website offers thousands of free books for students, teachers, and the classic enthusiast.
http://www.oswego.edu/~economic/newbooks.htm
This site provides online economics textbooks for topics like genereal economics, introductory economics, Macroeconomics, Microeconomics, and much more.
http://bookboon.com/
Bookboon provides online textbooks for students for subjects like accounting, ffinamnace, Biochemical Engineering, Biology, Calculus, Career, Chemistry, HRM ,IT Management, languages, natural sciences and many other subjects in PDF format.
http://www.ipl.org/
The Internet Public Library is a public service organization and a learning/teaching environment. The IPL has resources for various subjects like arts and humanities, business, computers, education, leisure, health, law and government, regional, science, social science and much more.
http://idpf.org/
The International Digital Publishing Forum (IDPF) is a trade and standards organization dedicated to the development and promotion of electronic publishing.
http://www.free-book.co.uk/
It is a directory of free online books. From romance fiction to computer language manuals, The site provides the most comprehensive listing of free online books available.
http://www.planetebook.com/
Planet eBook is the home of free classic literature. The novels and books are entirely free to download..
http://www.questia.com/
It is full-text online library of over 78,000 books and 9 million articles on subjects like Psychology, Education, Law, Sociology, Anthropology, Political Science, and Economics and so on.
http://globaltext.terry.uga.edu/
It is an International Initiative; global textbook project seeks to provide access to free quality textbooks to students in developing nations.
http://www.nap.edu/
Most books published by the national academic press can be downloaded for free in pdf format.
http://en.wikibooks.org/wiki/Main_Page
It offers more than 2000 titles and offers access to open textbooks