I'd say try out different styles of Metal, you never know what you might end up liking.
Death Metal (band - album):
Vomitory - Blood Rapture
Deeds of Flesh - Mark of The Legion
Cannibal Corpse - Tomb of The Mutilated
Dying Fetus - Stop At Nothing; Reign Supreme
Necrophagist - Epitaph (if you like technical guitars, this one's a must listen!)
Black Metal:
Endstille - Endstilles Reich; Navigator
Watain - Casus Luciferi
Immortal - At The Heart Of Winter
Marduk - Panzer Division Marduk; Serpent Sermon
Blut Aus Nord (even though they're classified as Black Metal, they have a very unique sound) - The Work Which Transformes God; The Mystical Beast of Rebellion
Ov Hollowness - Drawn to Descend
Infernal War - Transfigurations; Terrorfront; Conflagrator
Doom Metal:
Ophis - Withered Shades
Swallow The Sun - The Morning Never Came; New Moon
Black Sun Aeon - Routa
Isole - Bliss of Solitude; Born From Shadows
Comatose Vigil - Not A Gleam of Hope
Monolithe - I; II; III (yep, just Roman numerals for 1, 2, 3. Each album has one 50+ minute track)
Mournful Congregation - Tears From A Grieving Heart
Thrash & some other stuff:
Sodom (Thrash Metal) - Agent Orange
Nuclear Assault (Thrash Metal) - Game Over
Neurosis (Progressive? Metal) - A Sun That Never Sets
Amesoeurs (Post Black Metal) - Amesoeurs (self-titled)