http://www.wowio.com/ is a site that has free ebooks. the catch is you need an address that is non-anonymous. So gmail, yahoo, etc. will not work.
But it will allow you to download 3 e-books for free. There are only 3-4 knitting books. But still, they are free. Of course I already own one of them! *laugh*
(Though I haven't gotten the confirmation email after a half hour. Could be stuck in my spam filter. Gotta log into that account and can't do that from work. *sigh*)