http://www.australian-aquacultureportal.com/
AUSTRALASIAN AQUACULTURE CONFERENCE & TRADE SHOW
1-4 May 2012, Melbourne Convention & Exhibition Centre, Victoria, Australia
Not a goldfish or even a fish show, but many exhibitions and conferences on different aspects of fish care. Aimed at the commercial industry, but the hobbyist can pick up some interesting info and have a decent day too! If you are in the area at the time, probably worth a look. I may be around for a ay or two myself.