Controlling bigger motors with an arduino board
DC motors are typically driven with some sort of BJT/MOSFET solution that will be able to sink enough current to drive the motor because a microcontroller pin can only usually provide a few mA of power.  See this link for info on basic microcontroller DC motor control.  If slow response is acceptable and only one level of power is required (i.e. no PWM) even power relays could be used to turn on off the motor.  Some applications could use this.  However, for your application, it sounds like you will want more responsive control over the motor and need a particularly high power MOSFET to properly drive your application as your motor is very high power.  Such FETS such as these could be used to properly control such a motor using the microcontroller.  Do note additional protection circuitry will be necessary and is probably the topic of another feed, but this would be a place to start if you wanted to build it from scratch.  Otherwise go with an over the shelf driver board which will probably have something like the link above used on it.