LibriVox (https://librivox.org/) lets you listen to books, available on the public domain, for free. This service is similar to the eBooks available through Project Gutenberg (https://www.gutenberg.org/), which I wrote about last week (https://at-udl.blogspot.com/2019/05/project-gutenberg.html).
Volunteers from all over the world read the books published on LibriVox. The audiobooks are free for anyone to listen to. You can listen on your computers, an iPod or other mobile device, or you can burn it onto a CD.