Let me get you started:
- Hungarian/British composer Matyas Seiber: Wikipedia says he died of a car accident in South Africa, but I heard that he was eaten by a lion
- Jaco Pastorius was beaten to death by a bouncer
- Jean-Baptiste Lully died as a result of hitting himself in the foot with his conducting staff (used prior to the baton) causing him to get gangrene and die three days later
- Alban Berg died from blood poisoning contracted from a bee sting on his back
- Ernst Chausson was riding a bicycle, lost control and crashed into a brick wall, dying instantly
- Les Harvey, guitarist for ’70s blues-rock band Stone the Crows, died onstage in front of 1,000 fans on May 3, 1972 when he was electrocuted while tuning up for a show in Swansea, Wales.
- Terry Kath, lead guitarist for Chicago, accidentally shot himself in the head with a pistol