If you're referring to cycling tours in various spots in the world, I'd suggest you browse through the Touring forum, and then ask the question there if you haven't found an answer to your question.
http://www.bikeforums.net/forumdisplay.php/47-Touring


If you're referring to tours like the Tour de France, go to the Professional Cycling forum.
http://www.bikeforums.net/forumdispl...g-For-the-Fans