This is one of those deals that you jump on RIGHT NOW and then figure out the rest of the details later! Pretty much the entire US is on sale to New Zealand for around the $350 mark! That is an incredible deal that will not last long so book soon!
Fly to New Zealand From Almost Any City In the US for $340-ish!
This is from TheFlightDeal (check their post for all the details) and it is incredible! I am checking even the small airports that I have family near and the price is coming back at that price.
This will not last long! Also, I would hold off on booking any non-refundable travel for a few days in case the airlines decide to not honor the fare. While this is incredibly cheap, it is also not a business class ticket so I would guess that these would be honored.
Check the various online booking sites like Priceline, Orbitz and others. You can use Google Flights but they may still show availability even if it is not able to be ticketed. At least it will give you some dates to work with. It looks like this is good for travel from February through June, 2018! You may be able to find it as low as the mid-$200s as well, depending on the airport.