On my search for a motor which suits for me I found 2 I could use ( remember i'm searching for fast motors not ones with a lot of torque
motor 1 http://www.gizmoszone.com/shopping/agora.cgi?product=Gearmotor&user4=810series;ppinc=1g note- the first motor with the 2700 rpm.
motor 2 http://www.pololu.com/catalog/product/1093
The problem here is the first motor does not appear to have any compatible wheels or chassis whereas the 2nd motor has many compatible wheels and chassis.