LibriVox - public domain books podcasts
LibriVox is a project which objective is to make all books in the public domain available, for free, in audio format on the internet (generally podcasting). It has a database-driven catalog where every podcasting project can be found using the search page.
Once you have found and clicked the link for a book/recording you want to listen to, there are several things to note about the individual catalog pages. Each catalog page contains a description of the book, and helpful links about the book and author. You can also find a link to an online source for the text, if you wish to read along.
You'll find that you can download files in several places. You can download the individual chapters by choosing 128kbps MP3, 64kbps MP3 (smaller file size), or the Ogg Vorbis files. You can also find a link to a zip file of the whole book at the top. Another option is to find the recording with !BitTorrent, but not all recordings have been seeded.
The first step before you listen is to get the audio files onto your own computer. Once you have found an audiobook that interests you, there are many ways to download the files, and save them onto your computer. Each chapter is offered in three (3) formats: 64 Kbps MP3, 128 Kbps MP3, and Ogg Vorbis.
The audio files are hosted by the Internet Archive (see http://www.media-and-learning.eu/resource/internet-archive)
It is a totally volunteer, open source, free content, public domain project.
Librivox contains books in English, German, French, Spanish, Italian and a few other languages.