There are 3 clubs in Auckland so I am not sure which one is closest to you. I gather you have seen the club list with contact details. Paul Monckhof, secretary of one of the clubs, is away at the moment as he is in the NZ champion boccia team and they are building up for the next championship (or the disabled games, I can't remember which) so it would pay to contact the president of that club instead, if it was the closest to you.
The Auckland clubs have inter-club shows, or competitions, but we do not often have large fish shows these days as they are very expensive to run, and get to! The last one was a public display in Napier, organised by the Hawkes Bay club. We took a van load from our club to the event and thoroughly enjoyed ourselves.
You may have seen elsewhere on the site that this weekend is our annual conference. It is being held in Blenheim this year with me organising it so check out the chat room during the weekend as we hope to be in there during the evenings after dinner. We may even get a web cam set up.