Jim Norton is obviously a big oldschool metalhead. He even got fucking Lemmy to play his acts on in his show Down and Dirty with Jim Norton.
Celebrities who most likely listen to metal: Robert Rodriguez, Quentin Tarantino, Seth Rogen, Danny Trejo, John Waters (pornogrind), Kenneth Anger, James Wan (director of Saw), Paul Thomas Anderson, Sid Haig and Rupert Grint.
Also, totally unrelated note, James Wan is currently directing a Castlevania film.