The biggest bit of homework I could give is go to 5-10 Atuox's. You WILL bring your car to its maximum handling potential and then understand more things about the car and what you really want to change in order to make you faster. A well setup race/autox car is almost scary on the street, and its definetly a challenge in inciment weather.
I will tell you every winter I learn more about my car...I make sure I go out and drive around in the snow before they plow, it helps bring me back to basics, Brake in a straight line, gas at apex, etc. Its all about know what the car while its at its limits then the driver adjusting for it.
Start reading then start
There is alot to take into account when your dealing with this black art.
I am out for the night LATER