Anyhow, I was poking around online today and came across this:
LibriVox provides free audiobooks from the public domain.
Well, you can't beat free. They don't have a massive catalog, and I've read a lot of what they do have, but there are a few things I might download later and listen to, like Right Ho, Jeeves. Plus, there are some things in the works that I might check on once they're finished ... like Don Quixote in English and Spanish! (This is very meta if you read Megan's blog.)