LibriVox volunteers record chapters of books in the public domain, and then they release the audio files back onto the net for free. All their audio is in the public domain, so you may use it for whatever purpose you wish. Volunteering for LibriVox is easy and does not require any experience with recording or audio engineering or acting or public speaking. All you need is a computer, a microphone, some free recording software, and your own voice. They accept all volunteers in all languages, with all kinds of accents. You’re welcome to volunteer to read any language you speak, as long as you can make yourself understood in it.