Getting to the Root of Wasabi (genuine wasabi is a rare find)

Boston.com

For some people, a trip to the sushi bar is just an excuse to experience the kick of wasabi. But the pleasantly pungent green paste served in this country is rarely made from actual genuine wasabi root; more often it's regular horseradish doctored with food coloring. How can you get the real thing? Short of growing your own, the easiest route ... (Full article)  

http://archive.boston.com/ae/food/articles/2005/09/28/getting_to_the_root_of_wasabi/