Ticketmaster is an event ticket seller, listed at Level 1, 23 Customs St E and under Rocky Bay on Waiheke Island, with a Google rating of 1.4. Its New Zealand website is ticketmaster.co.nz. Customs St E is usually associated with central Auckland, so check the address before you travel.
Ticketmaster is a large international ticket seller, so most business is done online or by app, and not at a counter. Buy only from official sellers, check the event, date, venue and seating before you pay, and look at what booking or service fees are added at checkout. Popular concerts and sports events can sell out fast, so regulars join pre-sale lists or newsletters and log in before tickets go on sale. Keep your confirmation, and check the refund and transfer rules in case plans change. Avoid unofficial resale sites, since fake tickets are a risk.
For people in Auckland and on Waiheke Island, Ticketmaster is where many events sell tickets, and its website is the best place to start.