First off, here are a couple other threads that might help you in your uograding:
Club Reviews: http://www.wgt.com/forums/t/72948.aspx
Club Chart: http://www.wgt.com/forums/t/72459.aspx
I'd agree with the wedge purchase. Get 3 and dump the hybrid, though. I'd say get a 64, 60, and 54 or 56 (that choice depends on what iron set you plan on upgrading to). At L37, I'd recommend you have a look at the L35 Ping G|10 Irons, they're one of the best values in the pro shop. The Pro driver is ok for now. Also, have a look at a putter. I'd recommend getting in the Ghost Spider line, but if the price points are an issue, shop around. Tour-SD balls would probably be a good ball at this point, and you shouldn't have too much trouble earning enough credits to make that work (you'll be surprised how fast you earn them once you get good at it). Be sure to invite some of your friends, too. You get a free pack of Srixons for every one who signs up!