Great to see Loren Mazzacane Connors, Derek Bailey & Mary Halvorson cited above, and I share great admiration for all those others named, perhaps especially John Fahey, Richard Thompson and Nic Jones.

I'm going to try and go with some that haven't been named yet -

3 in folk-ish idioms:

C Joynes
Ben Chasny
Jack Rose

3 in other realms:

Keiji Haino
Sonny Sharrock
Christina Carter