You can get this one for free at Claudio Vianini's website (following the link "games"). You get a 21-page .doc file with the rules (in italian) and a lot of graphics to make the road and the riders. Even if you don't understand Italian, it's worth a download. You never know what you can use the graphics for.

The rules of the game, on the other hand, are nothing special. You can choose between four levels of difficulty to play, each one adding some new elements to the game, but it's just a dice game after all. I have to admit, though, that I have not played the game (I have only read the rules). There are better games around, even better dice games, but they are not free.

 

Some of the tracks: