PA28181: I tried to get a flight from a club at Picton, (can't remember the name) but typical NZ they were all going home in the afternoon.
There's no club or any flight school at Picton.
I'm not sure what to make of your other comment. You make it sound like New Zealand closes up in the afternoon, which is most certainly not the case.
Any club or school I know of is open till 5 pm and very often much later unless they only operate part time then it's usually just weekends.
Destinationsky
If you get to fly with the Wakatipu Aero Club see if you can do a dual flight to Milford Sound. It will blow your socks off.