While meandering around the NYT today in the book section, I discovered two sites I wasn't previously familiar with.
lulu.com has books on demand and e-books. Any books that are in both print and digital format have no DRM. E-books only may or may not be protected, depending on the author.
podiobooks.com is a site that offers free audiobooks as podcasts. There seem to be a range of genres available. Authors apparently use this format to expand their audience.
The NYT article is here -
http://www.nytimes.com/2007/03/01/bo...html?ref=books
(may require free registration)