I reckon you're looking at $1000 including software but excluding the laptop, basically; say $100-150 for decent headphones, $200-250 for monitors, $100 for a w

I reckon you're looking at $1000 including software but excluding the laptop, basically; say $100-150 for decent headphones, $200-250 for monitors, $100 for a workable MIDI controller, $150 for an audio interface (something from M-Audio or Focusrite, say). That leaves around $350-400 for software, a cheap mic, stands, cables etc. (And you'll probably want at least one more controller, whether a Launchpad-style thing, a fader box, or Akai pads.)