This and this. When turning in the wet, use balanced (by this I mean keep the engine revs constant and leave the gear stick alone if its a manual) and conservative throttle: it's not very exciting but it should keep the car facing the right way. Acceleartion (not speed) causes cars to skid or spin. Remember that acceleration is at its highest in very low gears, so when you're accelerating in 1st or 2nd, this is when the rear is most likely to let go, especially in you're turning.
Same goes for braking. You can get away with hard braking much more if you're not turning. If you're braking and turning sharply, be prepared to touch cloth.