When I'm just trying to level up, I pick the recipes that use the smallest amount of materials that are at the "orange" level for me, and avoid the ones that use leather, flux, gems, or any of those other expenses (since I'm a miner, I don't consider metals expenses). Early on it was copper bracers, went through a few other items, right now (125) it's rough bronze leggings. You can read through the blacksmithing tradeskill page (selected on the left here) to pick the appropriate recipes to learn.
Good luck...
Edited, Mon Sep 19 11:06:09 2005 by fledarmus