Agalloch are good, they're a little like a mix between Opeth and Katatonia, which so forth leads me onto Katatonia, who are cleaner than Opeth and Agalloch in vox, but still a good listen.

You could try Hypocrisy, as well, which SOME consider to be melo-death. Heimdall will likely spread his opinion around here, too. My suggestion is that you listen to whatever advise he gives -- he's never steered me wrong in the aspect of music.