i'd second Dissection and Arcturus, quite amazing, i'd describe Arcturus as Techno/Black Metal/Classical band, they're amazing. Tristania aren't really black... and i don't really like them....
if you want something black, try Darkthrone, Emperor, Enslaved, Satyricon, Vinterland, Graveland, Vintersorg (somewhat reminiscent of Opeth, SOMEWHAT), Limbonic Art, Carpathian Forest, Borknagar, Ulver (was black on one album, the magnificent "Natterns Madrigal"), Rotting Christ, BURZUM (something else completly), Dodheimsgard and Immortal (probably the most technical of the Norwegian black metal bands)