In Flames are "American sound?" maybe their later stuff, but their earlier work? no way (it still sucks, but i'm guessing most here would disagree with me there)
anyway:
Emperor - In The Nightside Eclipse, Anthems to the Welkin at Dusk
At The Gates - The Red in the Sky is Ours
Arghoslent - Incorrigible Bigotry
Ulver - Bergtatt
Summoning - Dol Guldur
Sacramentum - Far Away From the Sun
The Chasm - Deathcult for Eternity: The Triumph, Conjuration of the Spectral Empire
Nokturnal Mortum - Lunar Poetry, Goat Horns
Burzum - Burzum/Aske, Hvis Lyset Tar Oss (vocals take some getting used to)
Deathspell Omega - Si Monumentum Requires, Circumspice
Immortal - Pure Holocaust
Judas Priest - Painkiller
All these bands are pretty melodic, which I think is what you were shooting for.