Did one last year. When you get off the ship turn left out of terminal. Follow road straight for about 100 yards. Do not turn with the road, ahead of you is a fence with a small gate. Leave by this gate and straight ahead two streets. Take bus to nearest Brooklyn subway then subway to Grand Central. New York is then your oyster. Journey from terminal to Grand Central will be around 30 minutes. Have a good shop. Richard .
Head for Macys - 34th St and Broadway. If you go to their customer services with your passport you get a card that will give you a discount on everything you buy.
Thank you both very much for your helpful answers. I shall shop till I drop!!