I came across this link today for free photography e-books. There seems to be a diverse range available so I thought it would be worth posting here. Sharing of the link is encouraged via Facebook,Twitter & Google+ so I've done that as well.
http://www.photofidelity.com/blog/20-free-photography-ebooks.html
http://www.photofidelity.com/blog/20-free-photography-ebooks.html