If it were me I'd get an APC 40 ($300) and an Oxygen 25 keyboard ($100).
APC 40 integrates so nicely with Ableton Live. I mean that's why it was built. Plus, it gives you knobs and continuous rotary encoders with LEDs, something the Launchpad doesn't have. I own a Launchpad, and while they're awesome, I still can't help but wonder how much better my life would be with an APC 40.
http://cdn1.ableton.com/resource/ec0...0c2/top_on.png
The Oxygen 25 keyboard is nothing fancy, but it does the job well of having to enter notes. It's fun to work with. I'm not a really good keyboard player though. I'm coming from a guitar background. If you are a trained pianist you might want something larger and with weighted keys.
http://www.dancetech.com/aa_dt_new/h...mkIII_main.jpg
