I have some comments to David Kirkdorffer about purchasing midi controllers:
The launchpad is a very good controller, but for me it would be much to limited. I have often played with it at music stores only to discover it's shortcomings. I guess its appeal would be its simplicity, solid construction, and built in "keyboard". I recommend checking out the Doepfer Regelwerk. It can send virtually any midi command, has 24 programmable sliders, a built in analog sequencer (which is great for drum n bass sequencing with a sampler), memories, multiple midi ins/outs, Roland sync, and even a whole bunch of CV/GATE outputs for analog synths. I have version 1.5 which is so far pretty good but it still has a few glitches. v1.6 is coming out next month. I upgraded it from 1.2 over the internet and blew my own Eprom. Version 2 is suppose to blow 1.x out of the water. No exact dates on its release yet. Anyways check out Doepfer's midi control boxes. They may not be for the timid musician but they are super powerful for the money. I paid only $450 for it.