I didn’t know about... “LibriVox - Acoustical liberation of books in the public domain”
LibriVox is quickly becoming a valuable focal-point for so many things related to the Founders, it just required someone to commit to making it happen.
Browsing the keyword freeperbookclub you can find a lot that is not just directly the Founders themselves but also generals like Frederick William von Steuben, historians living in that era like Mercy Otis Warren, and many more.
https://freerepublic.com/tag/freeperbookclub/index