There are 10 courses in all, but you can race them backwards and forwards, Ridge Racer style, making for 20 available set-ups. As far as modes go, there are only three:
Regular race is your typical "point A to point B" event to the finish line.
Time attack has you post your best times for each race (which are then compared to your friends online).
Knockout is a multi-lap race where the last place driver is eliminated once each go-around is completed.