One of my favourite novels, H. Beam Piper's _Little Fuzzy_ is in the public domain (because he died intestate and the Commonwealth of Pa. failed to renew his copyrights before they were turned over to his estate).

There is a professional-quality reading of it by Tabithat:

https://librivox.org/little-fuzzy-by-h-beam-piper/

which I recommend highly.

Unfortunately, the quality of the readings can vary widely, and my family has often been unwilling to put up with a poor quality recording on long trips.

That said, I use their app on my phone while doing boring tasks at work, and greatly appreciate the project.