Audio Books

I checked out both Overdrive and Project Gutenberg. Overdrive let me search for books without setting up an account. It gave me the libraries where I could find an audio book located. I searched Project Gutenberg and found a history book I may be interested in called "Shiloh" as Seen by a Private Soldier. I don't think I was able to utilize these sources very well, I need a little more help in this area.