When I'm looking for a book that I think might be in the public domain, Project Gutenberg is always the first place I'll go. Not only do they have over 20,000 books, but they usually have the book in a variety of formats (at least plain text and HTML). Everything is always meticulously organized, and there are always several mirror sites to choose from when you're downloading something.

Reportedly, they go out of their way to make sure every book they post is in the Public Domain, so you never have to worry when you're getting something from this site. Also, consequently, no file has any attempt at DRM, lock downs, streaming, etc. They're all just regular downloads.

One of my favorite parts of the site has always been their Top 100 page. You can see a list of the most popular books of the day, week, or month. Usually there are some pretty eccentric top downloads, like the "Manual of Surgery." But there are consistently some greats like The Art of War, Ulysses, and Alice in Wonderland, to name a few. Another interesting page on the site is: Recently Posted. Here they list the books that've been added in the last day or two. According to Wikipedia, they can get about 50 books a week, so there's always something new to check out here. Some other interesting bonuses of the site are The Audio Books Project and The Sheet Music Project.

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