ManyBooks.net offers 29,000 ebooks for multiple devices for free. Their most popular downloads are The Art of War by Sun Tzu, The Adventures of Sherlock Holmes, a English grammar book from 1851, Lovecraft, Hugo, Shakespeare, Twain, and of course, Kama Sutra (how nice–blah). You’ll find new releases here.
Thanks for this.
In the same vein, http://librivox.org/ has free downloads of public domain audiobooks. You can also volunteer to help record additional works. I have downloaded such disparate authors as George MacDonald and Zane Gray to listen to while on the treadmill. I also have a converter to play my mp3 player through the car stereo so I can listen to audiobooks while driving.