The one guitarist who made me want to pick up a guitar is Black Sabbath's TONY IOMMI. Nobody, and I mean NOBODY riffs like the Godfather. Not a bad soloist, either.

The next nine faves, in no particular order, are:
Jimmy Page (Led Zeppelin)
Ritchie Blackmore (ex-Deep Purple, Rainbow)
Tom Warrior (Hellhammer/Celtic Frost)
Mantas (ex-Venom)
Johnny Winter (blues)
Angus Young (AC/DC)
Michael Schenker (ex-UFO, MSG)
Rory Gallagher (blues rock)
Keith Richards (Rolling Stones)

honorable mention: Randy Rhoads, Tommy Bolin, Steve Howe, Steve "Lips" Kudlow, Joe Satriani