PocketPC Addict found this useful site for free ebooks. Many of the etexts are from the November, 2003 Project Gutenberg DVD, which contains the entire Project Gutenberg archives except for the Human Genome Project and audio eBooks, due to size limitations, and the Project Gutenberg of Australia eBooks, due to copyright.
The books are available for PocketPC, Palm and Symbian. Categories include computers, science-fiction, non-fiction, and more.