Start game normally and choose the Rookie starting area. Accelerate car, while holding down the "B" button to about 25 - 50 mph and steer the car so that it is riding on the left shoulder of the road. Keep holding down the "B" button.
Eventually, you will hit a tree which is growing on the side of the road. When you do this you will see a digitized picture of one of the programers and a short message.
You will also see in the upper right hand corner a number. This is the level you are on. Use the OPTION 1 button to move the number forward, and OPTION 2 to move the number backward. (Note: gently tap the OPTION keys. This function really zooms thru the levels.)
Once you get to the level you want to play, press the "A" button. You're now back in the game. you will now continue to finish level 1, then the next level will be the level above the one you chose, i.e. if you picked level 48, after you finish level one, you'll be on level 49.