Most likely your front brake rotors (or discs, if you prefer) are warped.
This usually occurs from being overheated - just resting your foot on the brake pedal while going down a long hill is enough to do this - then when you stop the heat is trapped inside the rotor at the points of contact with the brake pads and so they cool unevenly, creating stresses inside the rotor that cause it to bend.
This can be repaired by either replacing the rotors or having them machined back to true. (Machining can only be done once or twice though, as there is a minimum thickness determined by the designer before the rotor becomes unsafe to use.) It's usually best to replace brake pads at the same time as they will not be as effective if they have been overheated, and they will also have a pattern worn into them that may create adverse wear in the new rotor surface.
If your steering wheel is shaking you probabley messed you wheels or axel up
Your brake rotors are warped.
Most probably
My steering wheel was shakey and worse when I hit my brakes. If this is your situation, it's alright to drive, but you need to have your rotors turned. They tend to warp when they're hot and the water from the rain hits them over a period of time.
look for play in the swivels and wheel bearings and at the busses - steering damper shot
Worn steering parts.
The power steering pump provides the pressure for the steering and brakes. Check the p.s. fluid.
On a 93 it is a lever located on the bottom of the steering wheel column. Bang your knees on the bottom of the steering wheel column and you will proabbly hit it.
suspension your steering dampner has gone bad, replace it and the shaking will stop.
the damage may be more than your steering wheel. you need an alignment
remove horn cap undo nut untill it is at top of shaft do not remove completely pull on steering wheel and hit it with a hammer
To recover from a slide on rainy roads, ease off the accelerator, steer in the direction of the slide, and avoid slamming on the brakes. Keep a firm grip on the steering wheel and be patient as you regain control of the vehicle. If you start to skid, try to remain calm and make small adjustments to your steering to straighten out.