A vehicle like that may be different from doc's robots, because you may not want to drive to the end of travel to reset, and you may want to be able to keep resetting (to compensate for drift, while it's driving)
My suggestion would be to put a cam on the motor, and have it hit a touch sensor when the motor is centered. When it's first started, you may use doc's second method (drive to end at low power) to make sure it knows which direction the touch sensor (center) is. Then, drive until you reach the touch sensor.
---> Link to lots of MINDSTORMS stuff under my picture --->