Behringer U-Control - Live Program

Hey All!!!

Firstly, I've got no idea where to post this.

I am a live musician (well I'd like to think so). I bought a behringer U-control keytar thing off ebay a couple of years ago to get down with some retro '80's keytar soloing on stage. Unfortunately, it is just a controller, which means if I plug it into my roland, I can play the exact sounds dancing around the stage. I'm looking for more...

What I'm looking for is a program I can install onto a laptop, and plug that into an amp or PA with the Behringer plugged into the laptop, and control live sounds... So if I'm looking for a particular instrument that I don't have on my roland I can dial it up on the laptop and play it live...

Does anyone know any simple programs I could purchase to accomplish this. If I've rambled and you have no idea what I'm talking about please let me know and I'll clarify.

Cheers!

junoskinner