As mentioned in the first response to this question and echoed throughout this thread...

Go meet with people in your area, ask for a ride and try it out. Cat sailors are very freindly people who will go on ad nauseum about thier boats and thier sport (I know I do). We all have our biases and most of us have not met or sailed with you can cannot give you the best advice.

If you are willing to wait until you find a good fit, take the time to sail with people. Like these guys have said, they are always looking for good, lightweight crew. I'm sure there is someone in your area that will be happy to train you and show you the ropes.

Again, just get on the water and try a few boats out before you buy.