Hi Johanna, here's a link to a NZ website for subscribing to the magazine: [
www.isubscribe.co.nz]
Also, the insert in my old National Geo mags (I last got them in 2001) is addressed to Freepost 4734, National Geographic Society, PO Box 798, Auckland. The fee for a 12-month sub is listed as NZ$65, the same as the price on the above website. The form asks for your name, address, and payment by "bill me", or "cheque for NZ$____ is enclosed, payable to National Geographic Society", or "Charge my __ Visa __ Mastercard. Account No.__ Expiration Date:__ Signature___"
Be aware that when you unsubscribe, they will hound you for quite some time in much the same way as Reader's Digest does.