Gillian Welch and David Rawlings. Probably my favorite sad voice and guitar.
… ever day is getting straighter.
Times the revelator
If you like the embed, try out this 10-year-old live clip of Annabelle.
Time the Revelator
Recent additions:
Red Clay Halo, good for any gardener dealing with clay soil:
Caleb Meyer
I saw them at Austin City Limits about 10 or 11 years ago. It was a great show.