Slayer - most anything but "Angel of Death" is a good start
Bongzilla - Salvation, H.P Keefmaker
Kyuss - they are kind of upbeat with heavy riffs so i dont know if you would want that but 50 million year trip and Green Machine
Monster Magnet - EGO, The Living Planet is about as heavy as you can get
Anthrax - Inside Out
Rob Zombie - Superbeast
Marilyn Manson - The Reflecting God
Soulfly - Pain, Bring it, Terrorist, The Prophet, Back to the Primitive
Most anything by S.O.D. (Stormtroopers of death, incase you find anything under the title of SOD)
Motorhead - Orgasmatron
and damn spectre, im really missing my pantera cds right now seeing those songs up there
