Low end (but still works great)

TQ3 Rx/Tx $35.00
MOPED ESC $35.00
Integy Lathe Motor $18.00
Tower Pro MG 955 servo (200+ oz's. of torque) $20.00
2/3 A pack from a RC18 $20.00
Pirahna Battery Charger. $50.00

High End

DX3 $199.000
Mamba (Max or 25) $145.00 - 75.00
Hyperion z3013 Brushless Motor $80.00
Hitec HS-5955TG servo $115.00
2/3 A Elite 1500 6-8 cell pack $32.00 or a small Lipo pack $40.00
Hyperion EOS 5idp AC/DC Charger (charges Lipo, NiMh, NiCd, Lead Acid) $115.00

You can see that there is a wide range of parts and prices available. And don't be afraid to mix and match. I use a Spectrum DX3 w/ a Mamba Max ESC, Axiom Lathe motors, Tower Pro servos, and Elite 1500 2/3 A packs.