CState -
For Panel lines, I just use a sharp #2 pencil and then weather the panels with pastel dust.
Here's a pic I posted previously of the technique on a 1/72 Hornet. Pretty easy.
If you're careful, you shouldn't come out of the recesses to often, and if you do, just erase it, or if you lined it up right, it can look like part of the weathering. BTW - I do this on the initial flat coat, before the gloss coat for decaling. The gloss coat and final flat helps get rid of any shine the pencil lead might leave.
Archer out.