The Flatt & Scruggs show (which was one early version of the Grand Old Opry, sponsored by Martha White Flour) is fantastic -- I'm not sure how much of it is actually available, but there are several volumes available on amazon, and the first 8 volumes are streaming on Netflix.
But to be honest, the biggest impact Earl Scruggs had on our household is in the kitchen. We heard that a biscuit recipe of his had been printed for many years by Martha White, and I finally tracked it down in their cookbook. We made it just for fun...but it actually is the best recipe I have ever used -- just look at the results!
Biscuits are a regular feature on our table; sometimes as a side but honestly, most often as dinner (with sides of homemade sausage and a lot of honey and syrup.)
The recipe has been replaced on their site with a new version that uses crisco and is now just called "famous" biscuits so here's how I make it:
Earl Scrugg's Famous Buttermilk Biscuits
First, melt 2 T of butter and set aside, and preheat oven to 450F
You will need 2 cups Self-Rising Flour OR
2 cups flour + 1 T baking powder + 3/4 t salt
To that add 1 t sugar and whisk (or pulse in a food processor)
Add 1/3 cup butter, chilled and cut up and either pulse in processor or cut in with pastry cutter until the mixture looks mealy.
Add 1 c buttermilk and stir in until it's shaggy looking. Turn dough out onto floured surface and knead until smooth (don't be afraid to sprinkle extra flour in there); roll out to 1/2" and then cut into rounds. Place on baking sheet and bake in oven for 12-15 minutes. When golden brown, remove and brush with melted butter. Put on some Foggy Mountain Boys and enjoy.