Reading the receiver is easy, you can find all you need on my blog starting here - http://rcarduino.blogspot.com/2012/01/how-to-read-rc-receiver-with.html
Controlling the motors may or may not be as easy.
If the motors are RC Hobby quality, they are probably powerful and will require a lot more power than Arduino can deliver, in this case you might want to use RC Electronic Speed Controllers, the good news is these can easily be driven by an Arduino.
If the motors are less powerful toy type motors you can drive these from an Arduino with a few cheap and easy to use components. Two common options are 1) Using transistors to switch larger currents from the Arduino or 2) Using a ready build motor driver chip.
If you come back with the type of motor, we can give you a better idea of what you will need.