I assume you have vocals already?
If not I will jump on that position.
myspace.com/dagalur for some low quality black metal recordings with me on vocals. You could get a good idea from this but we Also we have 1 better recording here http://lenniebudgell.com/music/halls%20of%20mandos.mp3

The other guy in the band can do black metal guitar.

I also play keyboards (not super duper professional or anything)

Anyways listen to those tracks (sorry for quality, neither of us drum) but he was guitars / drums and I was keyboards and vocals. Let me know if interested in either of us, email lbudgell@gmail.com