I agree with davidj, hobbies are expensive. Now since you allready fly plane you probabbly have most of the tools and field equipment required to fly. An electric starter is a must. Then, you need a starting wand. Allen wrenches, screw drivers, pliers, ball link pliers (optional), pitch gauge (required), fuel pump, ect. Most likly all you would need would be the pitch gauge and the starting wand. Then you need a radio, I would recomend an Airtronics RD 6000 as bare minium. It has 5 point curves, two P-mixes, and the other NEEDED helicopter porgrams like idle up and throttle hold. I would recomend AT LEAST cheap ball bearing standard servos. You can get by with a non heading hold gyro but at around $200 for a Futaba 401 gyro AND digital servo I don't recomend it (if that was confusing, I am trying to say the Futaba at $200 is VERY good).

So let's see...
Hawk Sport, $159.99
Thunder Tiger, $109.99
Airtronics RD6000, $279.99
ACE Starting Wand,$13.99
Helimax Pitch Gauge, $25.99
Oh, yes, and the gyro, $200



Hours and hours of fun, PRICELESS.

Your looking at around $800 + shipping which usually isn't too much and is sometimes free. Sometimes you can save if you find a good used setup. Now is the time to do it! It's an RC Buyer's market! Lot's of items being sold and not a lot buying.

If you allready have a TX that can do helis then a good Futaba flight pack is around $100 from tower. That's what I did, saved me money until I got my good ol' 9Z!