alt.guitar - join
You axed for it, you got it.
Low activity, 2053 subscribers, Usenet

rec.music.makers.guitar - join
Electric and acoustic guitar techniques and equipment.
Low activity, 1112 subscribers, Usenet

rec.music.makers.guitar.acoustic - join
Discussion of acoustic guitar playing.
Low activity, 1970 subscribers, Usenet

alt.guitar.effects - join
Low activity, 615 subscribers, Usenet

alt.guitar.amps - join
Discussion of guitar amplifiers.
Low activity, 1171 subscribers, Usenet

rec.music.makers.guitar.jazz - join
All aspects of jazz guitar.
Low activity, 1752 subscribers, Usenet

rec.music.classical.guitar - join
Classical music performed on guitar.
Low activity, 1164 subscribers, Usenet

rec.music.theory - join
A forum for discussion of music theory.
Low activity, 770 subscribers, Usenet

alt.music.makers.soloact - join
A forum for working Solo Musicians
Low activity, 286 subscribers, Usenet

alt.guitar.bass - join
Bass guitars.
Low activity, 809 subscribers, Usenet