Passed in 1982, the Official Information Act marked an important change in the accountability and transparency of New Zealand's government. No more would government information default to being kept secret, now the expectation was that it would be released to anyone in the country who asked for it (there are grounds for refusing - see the act for details).
Using the Official Information Act is very simple - you just ask for the information that you want. You don't even have to say that it's an OIA request.
However, website fyi.org.nz makes it even easier. It provides online access to 3030 OIAble public authorities from government departments to schools. Pick your target, write your request, and send it on its way.
Even better, the requests and their responses are stored and made publicly available on the site so that everyone can benefit from them (don't use the site to request private information). Remember to search before your submit in case someone else has already received the information that you require.
We like FYI and the Official Information Act so much we've added a feed of their latest responses to the feeds on our website.