Kotzen is the one for me, I like his voice even better than his playing.
+1 to Meniketti and Gilmour.
Warren Haynes - wonderful singer and player.
Jonny Lang - what an incredible voice that kid had, even on his first album when he was about 15!
Ty Tabor from King's X - not the strongest voice, but very pleasant and melodic.
Chris Cornell - mainly a singer, but no slouch on guitar.
Steve Marriott and Peter Frampton - Marriott more for the vocals, Frampton more for the guitar, but they were both very capable in all departments.
And some great singing bass players:
Jack Bruce
Geddy Lee
Phil Lynott
James Dewar
dUg Pinnick
Then there are loads of guys (like Gary Moore) who don't necessarily have amazing voices, but have loads of character and certainly get the job done. And guys who weren't originally the singers in their bands but turned out to be pretty good anyway:
Jerry Cantrell
Eric Clapton
Leslie West
Jon Butcher (anyone remember him?)
Jimi Hendrix
SRV
Richard Thompson
(the young) Peter Green
James Hetfield
Rick Derringer
Andy Powell
Jason Bieler
Nuno Bettencourt
(Showing my age here, aren't I? :lol: )