Audio Diversions Details
Store with audio books on cassette, cd, and mp3 to buy or rent.
http://www.audiodiversions.com

AudioMysteries.com Details
Rent mystery audiobooks on CD and MP3.
http://www.audiomysteries.com

Audiotogo Details
Audiobook rentals on CD or tape.
http://www.audiotogo.com

Books in Motion Details
Formats offered include cassette, cd and mp3. Includes links to author sites as well as tips for first time users.
http://www.booksinmotion.com/

Booksfree.com, Inc. Details
Uses a monthly membership model to rent paperback books as well as audio available in both CD and MP3-CD format.
http://www.booksfree.com/

JiggerBug Details
Audiobook rentals available on CD, cassette or by download.
http://www.jiggerbug.com

Kitabe.com Details
MP3 Audio Book rentals to members in the US and Canada.
http://www.kitabe.com

Simply Audiobooks Inc. Details
Content available on CD to the United States and Canada. Uses a monthly membership model.
http://www.simplyaudiobooks.com

The Talking Book Club Details
Has both a rental and buying model for audio books in both CD and tape formats.
http://www.travellerstales.co.uk