Too many to list, really, but some names that spring to mind (bear in mind that I'm old..!)...
Richard Thompson (Fairport Convention and more...)
Jorma Kaukonen (Jefferson Airplane, Hot Tuna...)
Bobby Weir (Grateful Dead...)
Paul Kantner (Jefferson Airplane...)
Mickey Baker (see his Jazz Guitar Method books...)
John Lennon (Some Merseyside group or other...)
Bryan Maclean (Love...)