Aside from the Bling-bling crowd, the only non-rapper I can remember getting murdered was that Latino singer, Selena. The president of her own fan club blew her away. Then there are the never-ending rumors that Kurt Cobain didn't kill himself, but that Courtney Love offed him. But that's about it.
BTW, Elvis doesn't count, since he's actually with the aliens on a UFO. ;^)
Sam Cooke, soul singer. Lee Morgan jazz trumpeter. Bobby Fuller, rocker. Carlton barrett, reggae star. Marvin Gaye, soul singer. Al Jackson of Booker T and the MG's, soul musician. John Lennon, Beatle. Don Myrick of Earth Wind and Fire, 70s cheese rocker. Felix Pappalardi of Mountain, rocker. Bobby Ramirez, blues rocker. Jaco pastorius, jazz bassist. Jim Sheppard, rocker. Peter Tosh, reggae. Mia Zapata, Seattle punker.