You can pretty much squeeze by with Bronze until you pick up various pieces of Darkforge in your 30s, primarily through grouping in Cazic Thule.
Allakhazam link.
This is coming from a rogue's perspective though, and what I've seen other SK's manage. I've never leveled one past 4 myself, so I'm sure a more seasoned SK will chime in with more helpful advice for anything you can pick up inbetween Bronze and Darkforge.