I watch a lot of drift videos because my 1 year old son loves them & they catch his attention long enough for him to fall asleep on my lap. My observation is that they are heavly modified cars. The front wheels will turn at least an extra 15 degrees & they have huge amounts of horsepower. I think it is just as entertaining to watch as freestyle motocross jumping. I woud think the learning curve to get involved would be very expensive. I'm jealous because I don't have enough power & have to wait untill it rains.
Here's a few.
http://www.gofastvideo.com/gallery/album/view/18