You going to need 3 things.
1. fast lens (f4 or faster)
2. fast focus speed
3. money to buy the above 2.

my recommendations: http://www.usa.canon.com/consumer/co...0&modelid=7345

or

http://www.usa.canon.com/consumer/co...&modelid=14260

also IS isn't necessarily necessary. you can use a tripod or a monopod. the blur that comes from tracking a subject wont be reduced by using IS. faster shutter speed will reduce/remove it. personally i prefer to track the subject and use a slower shutter speed to blue the wheels/back ground. I use a mono pod if I am standing in one place with VR (Nikons version of IS) turned off or set for horizontal tracking. If i'm not using a mono pod and/or on the move I turn on both but most of the time I don't see a big difference in the photos.