A great source for audiobook versions of public domain works, read by volunteer contributors. Listen online or download! This is the first place I go to for audiobooks.
A massive collection, Project Gutenberg is my go-to source for ebooks, which can be read online or downloaded. They also have some audiobooks!
A nice, easy-to-navigate website. You’ll find 100% delightful Classics here. For most books you can read or listen online, or download the audio or text.
Music isn’t the only thing on iTunes…there are also plenty of free audio books!
If you have a mobile device, Kindle and iBooks also have a wealth of free books available, espeically classics novels. An unlikely source, the “Podcasts” app also is a good place to look for audiobooks.