[Al Skierkiewicz]

Paul,
The connector that comes on the fan is a standard connector in many devices. The manufacturers provide that mating plug on their power supply or where the supply enters the main board for the device. You need to cut this connector off the wire so that you can add the needed crimp on terminals.
The fan you were looking at that had three wires is used where the system must know that the fan is turning. The third wire is a signal wire.
You can wire to a Spike via a 20 amp breaker and control the fan from your RC or you can wire directly to the breaker so that the fan runs whenever the robot is turned on.