Hi Amy,
There?s some info on banks and banking from previous posts
here and
here and
here .
Bascially, you don't
need to set up a bank account before you get to NZ, but you can do if you want to. Setting up a bank account, either from the UK or when in NZ is a relatively simple procedure. Some people set up an account in their home country and activate it when they get to NZ.
There's a list of bank websites on the Making the Move category in the Master Website List.