Good hip hop production tool for under $500

Hey,

I am looking for an affordable production tool to use with Logic, Fruity Loops and Cubase. What I want is to be able to use it as a midi controller, so that I can record using sound banks I have on my computer, instead of using my computer keyboard for midi keys, which is extremely hard to do well. A friend of mine uses a basic synth that he plugs into Reason for beats that he makes. I was wondering if I should just go this way or what my options are. Style of music is hip hop.  $500 is my ceiling and preferably it would be under $300.

Any suggestions? General advise on Cubase, Fruity Loops, and Logic would also be awesome. I have used production software for live instrument recording and editing, but never for hip hop production.

Thanks!

-Greg