There are a number of sites that offer eAudioBooks for free.

Books Should Be Free and LibriVox provides free audiobooks from the public domain.  

eJunto was created to bring historical and philosphical audiobooks to the public domain.

FreeClassicAudioBooks.com has a number of classics titles, and the site also takes requests.

What are your favorite resources for free eAudioBooks? Please share them in the comments!