Get Robes of the Lich? They have a pretty huge drop rate out of Razorfen Downs, you'd only have to do a couple of runs to get it. My warlock friend is 60 and still wearing those robes (39 blue). We give her a lot of crap about it, though. Still, the robes are great. Go get! (Even though you might be partial to your Bloodrobe. :-/)
I think my most preferred way to make leveling easier and more fun was to have a leveling buddy. Granted, it's a little late for someone to start catching up to you right now, but, I'm serious; with my warlock friend and my hunter self, we were plowing through two-three levels a day until our 50's, where we still pulled off on average one level a day. Not only does it go faster, but it's fun. We'd take on 5 mobs at once since we could, so it actually became a challenge instead of just a slow, boring grind.
At 57 we took a 60 elite. And we didn't even know it was an elite when we started attacking it. I say that just to state my belief that warlocks and hunters are the most insanely uber classes. (At least, in PvE.) And I like talking about it. Because it's a very firm belief of mine.
Be proud! You play a lock.
