Below, you will find links to all the tracks that I have created over the last few years for the amazingly cool series of Trackmania games from Nadeo. All of these games include a modular editor that allows you to quickly and easily create new tracks for the game.
I think that one of the reasons I enjoy making these tracks so much is because you can work on one of them for a few hours (say, over a couple of evenings) and end up with something very polished and fun. It's a nice relaxing shift from working on FPS levels that may take weeks or months to get close to a finished state.
Trackmania Nations is a FREE version of the game, and is only limited by including just one each of the seven environments and four play modes found in the full game.
If you like racing games at all, you should download Trackmania Nations and try it out. Right now. Seriously.
If you're going to try out any of my tracks for the original Trackmania (as opposed to TM2), I recommend the ones for Trackmania United, only because they are more polished than the older tracks and my TM building skills have improved over time. Also, any of the Stadium, Normal-Race-Mode tracks for TMU will work with the free version of the game.