From Tonic.com, this list of five places to download free e-books:
1. Project Gutenberg — The granddaddy of all e-book sites, Gutenberg contains the text of thousands of public-domain titles. From the Bible to the Kama Sutra and everything in between, they’re all there. And you can read their titles just about anywhere, be it your computer, your Kindle, your iPad, or your phone.
2. ManyBooks — Like Project Gutenberg but a little bit prettier, ManyBooks has about 26,000 free e-books just waiting to be downloaded. The site started out with e-book version of Project Gutenberg titles, but has expanded to include many additional public domain and Creative Commons titles from additional sources.
3.Tor.com — Tor is one of the world’s biggest Science Fiction publishers and they took the steps to embrace e-books years ago. Their website is packed with free books and stories from their best-known authors. Their logic is that if you read a book for free, you might also want to buy it in print. Your mileage may vary on that logic, but it’s still a great source for some good reads.
4. Amazon and Barnes & Noble — If you bought Amazon’s Kindle or Barnes & Noble’s Nook, you may as well keep shopping with them. Each of their sites offers hundreds of free books. They’re often the same books you’d find at the sites above, but you might also luck out and find that a publisher is offering its commercial e-books for free as a special deal through one of the online stores.
5. Your local library — What’s that, you didn’t know that your library has free e-books? Well, it all depends on how quickly your state’s library system is adapting to the electronic world. Some libraries have actual Kindles you can borrow, with e-books loaded on them, while others let you visit a special library site and download e-books to your reader for a week or two. (My library hasn’t gotten that far yet, but I can download audiobooks to my iPod any time I want.) Does your library offer this? You don’t know unless you ask.
I like Tor’s attitude a lot, because I think it’s valid — if I read an ebook for free, I actually just might want it in print, or more to the point, want more from from that author. And I have nothing but terrific things to say about Project Gutenberg. While Google Books are poorly scanned and horribly OCRd, PG books have been carefully proofread by teams of volunteers. Much better quality.