Here are some song titles:
Threshold - Fragmentation
Threshold - Echoes Of Life
Threshold - Falling Away
Dark Tranquility - Monochromatic Stains
Dark Tranquility - Treason Wall
Opeth - A Fair Judgment
Opeth - Master's Apprentice
Opeth - Windowpane (some proggish stuff from their new album)
Opeth - In My Time Of Need (some proggish stuff from their new album)
Arcturus - Kinetic
Arcturus - Nightmare Heaven
Andromeda - Words Unspoken
Andromeda - Crescendo of Thoughts
Soilwork - The Bringer
Soilwork - Natural Born Chaos
Soilwork - As We Speak
Nevermore - Tomorrow Turned Into Yesterday
Porcupine Tree - Trains
Porcupine Tree - Blackest Eyes
Katatonia - Criminals
This should get you started.. All of these bands have MUCH MUCH more good shit, obviously... If you haven't (which I doubt) heard of stuff like Testament, Pantera, Slayer - stuff that's been around since late 80s but is still good - I recommend you some of it. Testament's The Ballad, Disciples Of Watch, Return To Serenity. Pantera's Psycho Holiday, Cemetery Gates, The Sleep, Follow The Hollow... Slayer's Seasons in Abyss, Dead Skin Mask, Temptation - all old stuff, but is refreshing enough if you haven't really heard it (all song titles, btw)..