Hi, My wife is Japanese. I have not taken the ICE class, but it is remarkably easy to make sushi at home. You can find recipes on the web and buy everything except the fish at JAS Mart and the fish at Gramercy Fish (or others). Google the web for sushi recipes.
Also, there is a class advertised in the Japanese local newspaper on January 30th at the Sachi on Clinton restaurant from 5-7. Sachi's on Clinton, 25 Clinton St., (212) 253-2900, 5:30-midnight every night, appetizers $6-20, entrees $12-22, kushiage $1-6, all major credit cards accepted.