As others have said it's not easy.
this was probably my best effort at the Southport indoor GP.
Camera is a Canon 60D
Lens 100mm Macro
F-stop f/2.8
sutter speed 1/320
iso 1250
Light was dreadfull for high speed work so had to wack the iso up.
No flash (didn't want to put drivers off)
Basically you need a really low F-stop (low number not technically low, It's very confusing, I'm a newbie myself , look here if you really want to mess with your head :-)
http://www.usefilm.com/Photo_Forum/1/851590/), So technically the higher(lowest number) it is the more light it is letting in. Although this does lead to a short depth of field (the part that is in focus)
BEST bang for buck by a LONG way is
http://www.warehouseexpress.com/buy-...ii-lens/p12814
Fantastic lens for the money if your looking for a prime lens.
Also think about getting yourself a monopod, They are only about £15.00 and worth every penny.