If there is one group in Adelaide that any aspiring startup should join, that would be The Startup Club Adelaide. The group has get-together activities almost every month fostering networking, camaraderie, and collaboration. How you could use it for your own benefit will depend on how creative and engaging you'll be in building connections.
The last meeting I attended was March 20 at the Richmond Hotel Adelaide. I think to grow in the community, one must also try to attend as much as you can as that will allow you to get to the members better.
I hope that I'll get the chance to join one of the meetings again while I'm here in Adelaide for less than a month. If networking with entrepreneurs and startups is your cup of tea, join its Facebook group and start building relationships.