LibriVox - free public domain audiobooks
Audible - Audible is the world’s largest provider of premium audiobooks and spoken word content.
Mobilism.org - A home for book lovers, app enthusiasts, and much more.
Islamic Audiobooks Central - Listen to audiobooks about religion, spirituality and philosophy from the Islamic perspective.
Libro.fm - A digital audiobook platform for independent bookstores
LearnOutLoud.com - LearnOutLoud.com is the web's largest resource for audio & video learning.