eBooks

eBooks or eTexts are available in many formats. The free books are generally public domain or licenced under the creative commons copyright.

• Project Gutenberg - One of the oldest eText sights and hardest to use.
• ManyBooks.net - Yet another source for free eBooks.
• Inkmesh - A source for free eBooks and the ability to compare prices on non-free.
  
• Fictionwise - provides both free texts and ones that cost money.
• Baen Free Library - Free source for Science Fiction Texts

A general not on eBooks. There are now a lot of formats available.  For school, html format is often the best. It can be read by a web browser and requires no additional software.

Reader Software:

Microsoft eReader
Adobe Reader
Kindle Reader for PC
Kindle Reader for Mac
Sony eReader
Nook Reader Software - No Mac Yet

Free Books for Readers
Kindle Books
Nook Books