I’ve been exploring the Kindle ecosystem lately – a snapshot of some free download sources:
1. Amazon's now 18,000+ free books, sorted by:
"Bestselling" or by "Avg Customer Review"
2. Amazon's currently free Non-Classics - This one changes.
a. The link above is to Non-Classics sorted by BESTSELLERS.
b. Here are Non-Classics sorted by NEWEST books first.
3. "Big Deals on Kindle" - This one just doesn't change enough.
4. The Project Gutenberg e-books catalog (MOBI editions) for Kindles. You can search the catalog on your Kindle and click on one to have it downloaded to your Kindle from the site.
There are no Amazon charges on a download from the Project Gutenberg site.
5. A humongous Amazon Forum thread on a million or so books readable on the Kindle - How to get them (mostly free)