Here You Can Download The Game -Project Torque-
http://project-torque.aeriagames.com/

When playing multiplayer you have to get more and more points to be able to play more levels, in the beginning you can only play a couple, but as you get more points you can play more multiplayer levels. (you can watch the high level tracks as a spectator, until you get more points)

If you like TrackMania i think you will like this to, it's a Racing Game with many different Tracks and Cars. You can drive with others online or you can drive missions, take licenses and many other things.