It kind of depends what tree you want. You can pretty much dps and tank out of any tree. I been getting back and forth information on unholy spec being the high dps spec right now, but have not really tested the other trees to verify that. If your gear is low-end then, I would prob go with an unholy dps spec. Right now, I am using a 17/0/54 (which is a pre-3.1 spec), but still like and will eventually change my spec. As far as tanking, you again can use pretty much any tree. I believe that Frost may of been the tanking spec before 3.1, but not sure now. I have a link with a bunch of specs, but it advertises gold selling, so I believe I cannot post here, but if you can give me an idea of what tree you would like to work on, I can give you a dps or tanking spec for each of these.
Edited, Jun 10th 2009 1:47pm by Shadowflage