Check out - The Crooked Road - Virginia Heritage Music Trail. Its on the internet and discusses many music venues in SW Virginia. I had been to the Carter Family Fold (Store) in Hiltons, Virginia in the past, but on my latest trip I went to the Sunday afternoon old time jam at the Floyd Country Store. There are many other venues throughout the region that are listed on the website.
At the Floyd Store, they have 2-3 bluegrass groups on Friday night, but Sunday is the jam. About 14 musicians that played some songs I had never heard of but also played many that I knew. Good music, very friendly and the food is actually good and food and trinkets (tee shirts, etc.) reasonably priced.