Brian Welch, former guitarist of Korn became a Christian. I'd imagine he does Christian music. I can't check it out now as I'm listening to some meditation music, and to hear 'metal or hip' would do my nut in.
Lecrae is a great christian hip-hop artist. Along with Trip-lee. Not to sure about christian metal though. Go to pandora and type in lecrae for a radio station and it will bring up lots of christian hip-hop artists.
Oops! Forgot the hip-hop thing, sorry. Relient K is Christian hip-hop and I think they're really great. Might also check Deepspace5 & Knowdaverbs. The last one has gained a lot of respect, recently, in the Christian music industry.