My steering wheel shakes when I brake. I was told that it sounds like I need to have my rotors replaced. How much will it cost, ballpark, to have them replaced? Is it just the fronts and/or the back rotors?

Your car is practically new, I don't know what happened to your brakes, or rotors, but they usually go 100,000 miles before being replaced or turned. A brake shop will charge you a lot to do this, they make good money on brake jobs, a regular shop will get a few bucks less, it is a job, but not impossible. The first thing I would do is check the dim of the rotor, it has a stamp on it for minimum dimension, If it has never been turned, you can get them turned and get a new surface on them. The surface right now should look like it got hot, glazed, that causes the chatter, If there are grooves in the rotor from a rivet or ground down pad, not to worry, they just cut that part out. Some cars, the rotors come right off, some are part of the bearings, they have to be re greased and sealed before going back on, The price of new rotors is not bad, under $100 each, the cost to do a rotor/ brake job, should be $250, to be turned, not replaced, You can do it yourself for about $50 to $75. Pads and turned rotors. Check it out, Hope this helps.