I'm a kiwi and as the boys say, Queenstown is it, head late Aug or late june for best snow and least ice. Rent a house for the week, get a rental car and your set. Just hire your gear at a local shop and get lessons on the easier fields ie remarkables and not treble cone
Oh don't forget to bang the kiwi chicks and party, its a great place with heaps of other shit to do instead of skiing etc, best tip, just ski half days ie afternoons as you get absolutely rooted sking a whole day if your not used to it and the ice is softer....
Al