A ski rack consists of two parts, the mounting bars and the actual rack itself (the part that holds the skis). Some cars have a factory rack that you can mount a ski rack to (like my outback), some do not, and your car definitely doesn't. In that case you need to get a mounting kit specific for your car and then a rack that fits on top of that (the racks are universal, the mounting kits are not).
Go to thule.com and put in the make and model of your car, it'll show you everything you need, with different options. You can even order it online and install it yourself (not hard). Or go to a dealer and pick one up.
I have a pulltop 6 and I fucking love it. I can fit mad skis and snowboards on there which is good because living in denver means carpooling a lot. I usually go to the mountain with at least 3 other people. Also the rack pulls out so you don't have to reach over your shit covered car to get your skis. Keeps from getting road shit and sludge from getting all over your jacket. Might sound like a yuppie thing to do but believe me it's worth it. I used to have brown stains all over my jacket that wouldn't come out from road grime.