Faktor Tel the Australia based global voip provider is now offering nz did for as low as 5Au$ or 3.3US$ per month. This is the cheapest for which one can get a Nz did. Even the nz based provider are charging around 10 or more nz$ per month for a did. Currently only Auckland numbers are available.
And best thing is FaktorTel accepts international customers and payment with paypal also.
So guy get local in New Zealand & get your self a local number.