Well, the place I met most friends is the NZUnschoolers mailinglist:http://groups.yahoo.com/group/NZUnschoolers/
both supportive people from all-over, and friends right here in Wellington. Mind you, this is unschooling, so if what you had in mind was more school-at-home, this might not be for you. (It isn't radical unschooling, though, plenty in the unschooling groups use curriculum - when it seems suitable - and will guide the children in various ways, just following children's interests and not sticking to schedules for example).
Is there a local home educator's network nearby? That's also been useful for us.