Are you in a GT or GTS? If GTS its probably your rears squeeking. If its the front, have them checked. You may need your rotors to be cut. We have these things called shims on our brakes. If you are missing those they will squeek. Your pads could just be worn, there is stuff you can put on the pads to reduce this squeek.
As for the steering wheel shaking, its normal as long as its at excessive speeds. Its your tires. They could be balanced, but with all that physics bullshit and road conditions I would say that you are fine. If its doing it at like 50, you may have a problem. But the question is, does it shake real bad? Like, could it be just a normal type shake, or a shake like something is wrong.
YOu just seem to be having problems with your car recently. Hope things start to turn up for oyu. Good luick and keep us updated.