If your stopping and she is slippery out you want to use that transmission to slow you down as much as you can. If you have an auto from D to 3 to 2 to 1 untill you slow enough that you can stop without sliding.
DO NOT JUMP FROM D to 1 IN ONE SHOT......basicly this will slow your wheel speed to much and you will lose just as much traction as standard braking.
Also if your driving a FWD and you skid......drive where you want to go. Counter act the skid ( DO NOT BRAKE, your just going to lose control), and throttle through the turn. Practice in a parking lot and get used to the feeling so that you will just react when it happens.
Also practice threshold braking. Basicly what you want to do is to find the amount of braking that will cause your brakes to lock up, or when the ABS will come on. This is just driving in a straight line...accelerate, then stop as fast as you can without sliding. After a few tries your gonna find where that perfect amout of brake pressure is, and your going to find out exactly how braking distance your car is going to need when stopping in slippery conditions.
Now if your going to drive in whiteout conditions, don`t use your high beams. The light just reflects off the snow, and you will lose even more visibility. Use your low beams plus fog lights. If you still have a hard time driving after that keep an eye for the right hand snowbank. The snowbank is basicly the dropoff of the road, and it will follow the contours of the road most of the time. If you can`t see either, then find a safe place to stop and wait it out.
Got tons more, just ask.