Not complete at all...

Wave, Gothic, Electro, and similar

Deine Lakaien


The Crüxshadows


ASP


Mechanical Moth


Samsas Traum


Welle:Erdball


Schandmaul


Therion


Tiamat


Terminal Choice / BlutEngel


Sepia / Mantus / Black Heaven


Lacrimosa


Wolfsheim


Tristania


Project Pitchfork


Inkubus Sukkubus


Lake of Tears


Dreams of Sanity

Speed/Heavy Metal

Savatage / Jon Olivia's Pain / Circle II Circle


Blind Guardian


Savage Circus


Iron Maiden


Metallica (up to the black one)


Grave Digger


Accept/UDO


Gamma Ray


Helloween (up to Chameleon)


Iron Savior


Rage

Rock & 70's

Axxis


Axel Rudi Pell


AC/DC


Ozzy Osbourne


Nazareth


Dio


Uriah Heep


The Sweet


Led Zeppelin


Black Sabbath


Chuck Berry


Deep Purple


Bon Jovi

Classical

Bach


Bizet


Grieg


Beethoven


Mozart


(not really an expert there, but I like it every once and again...)