Hi!
Hobbyking provides a 'recommended electronics' section underneath the product itself.
For your motor, speed controller, and servos, they recommend the following:
Hextronic 6.2- gram servo (x4)
Hextronic 24 grams brushless motor (x1)
Turnigy plush 12A speed controller (x1)
The total cost for these electronics should be around $29.00 (USD) You can find all of the electronics listed above in the 'Combine related items and SAVE' section on the product page you linked.
If you do not have your own transmitter, receiver, and/or battery you will need that as well.