I’m actually based in Tauranga, but I spend half the week in Hamilton where my 2 co-founders are based.
Hamilton seems to have a reasonable number of software business, the ones I know of are mostly design shops or other service providers, not too many start-ups. There is one, MEA Mobile, doing some neat mobile apps.
Tauranga seems to be really trying to foster more of a start-up vibe. There are new shared-office-space facilities popping up, an active tech meet-up scene, and links established to US-based VC firms. It’s an awesome place to live & raise a family, so I have high hopes that the tech scene materialises & hope to get involved myself.
If you’re ever over this way, please get in touch, would be great to show you around & talk start-ups.