We have a access database seen here:
http://www.flickr.com/photos/27047719@N00/411506903/
We make paper scouting sheets that mimic the access form for 6 kids to record the match data, which is then fed into the database for calculation of averages and robot comparisons. Overall it is a lot of work, but provides us with really good strategical information as well as an almost instant list for picking alliance members.