Keith Shadwick, Jimi Hendrix: Musician (2003)
It's one of those books that you can't really fit on your bookshelf, but that's OK because Keith Shadwick's book, designed by Paul Cooper, is beautiful enough to leave around. Full of big pictures, but the narrative is just as good--and it features a section strictly on Jimi's equipment for all the guitarists out there.
Charles R. Cross, Room Full of Mirrors (2005)
Practically day-to-day at points, this biography of Jimi Hendrix by Charles R. Cross is undoubtedly his definitive biography.
Steve Waksman, Instruments of Desire: The Electric Guitar and the Shaping of Musical Experience (1999)
Good scholarship meets interesting subject matter in this in depth examination of the electric guitar by Steve Waksman. Jimi Hendrix is featured prominently in the chapter "Black Sound, Black Body."