Although I have a small collection of published music from 1800 through the War of Rebellion, i get the impression that you are looking for local, regional Folk music which seldom was written down or recorded, but passed on orally from one Generation to the next.

Alas, I probably can't help you much with that.

My suggestion to you would be to peruse the Library of Congress

US Library of Congress

and Smithsonian Institute

Smithsonian Institute

"Media" collections, many of which are on-line now.

Back in the 1930's, the Federal Government assigned WPA Workers to scout around in what was left of isolated rural Communities and collect the songs, stories and legends from any of the Residents who still remembered them, and record them for posterity.

Many of these songs were traced back to their roots in 18th Century (or earlier) England, Scotland, Ireland where many of the Appalachian Ancestors immigrated from, many of them prior to the American Revolution.

Over the years there were evolutions in lyrics and melody, but the connection was still quite recognizable.

Since then, others have ventured forth into the Hinterlands collecting songs with such recording technology as their time could afford. Many of these historical treasures were released in album form, most on "wax" LPs.

I'm not sure if they have ever been offered in more modern format, such as CD or digital files, but would not be surprised if they have.

At any rate - these primary repositories probably have the most extensive collection of just the sort of music that you are looking for.

Happy hunting!