Nelson Aviation College:
http://www.nelson-aviation.co.nz/
North Shore Aeroclub:
http://www.nsac.co.nz/
Ardmore flying school:
http://www.ardmore.co.nz/
International Aviation Academy NZ (operated out of CH International airport):
http://www.flighttraining.co.nz/
Christchurch flying school:
http://www.flyingschool.co.nz/
There's a few. Might pay to do a google search, there are heaps of schools!!