A Canon HV30 and a macbook seem to work very well. The important thing seems to be mounting it on a tripod about 8-9 feet up so you can get a better view of the racers. Oh, and do yourself a favor, make sure the refs remember to check the racers at the start for the numbers facing the wrong direction, being on the wrong side, etc. At the beginning of a season it seems that new racers are especially prone to having the numbers wrong and in some races you may have 636 and 939 or similar in the same race.
