Hi Lynne
Some of the main ones I know of are:
Alexander Turnbull Library - early photos and documents - same
location as National Library
National Archives - probates, Inbound ships, Coroners Reports there
for those deaths in NZ. - Murphy Street near old St Paul's.
National Library opposite parliament:
Wills for England
The electoral rolls
Surname index in the library which is referenced to NZ
magazines/papers and books.
1881 census and other census's under the county on the shelves, but
it varies