You can use code to drive servo controllers. The kind of motorcontrollers you show in that link, is fully compatible with it.
BTW These kind of motorcontrollers are PWM. They don 't really provide 0-14 VDC.
If the car needs to reverse, you 'll need another type of controller, called a "fyll H-bridge". Airplanes don't reverse...
And these kind of RC motor controllers can be bought very cheap on eBay. Have a look here, for instance:
http://cgi.ebay.nl/ESC-30A-RC-Brushless-Motor-Electric-Speed-Controller_W0QQitemZ140140310061QQihZ004QQcategoryZ294QQcmdZViewItem