I am very new to this and have only been to the one track - Lakeside which is on the north side of Brisbane. I had my first track day there last weekend which was great.
On the south side I guess the closest would be Archafeild which im still to go to. If you go into the forum for Pocket Bike Clubs or do a seach for Archafield you should find heaps of info.
Otherwise the members that I know race there are Grayzwun or Morty. Both will be helpful.
Im sorry I dont know more, it's just that im quite new to all this my self.
There is a club just near you(i think).. It is Wollogong City Raceway..
However be sure to contact the club as I believe that they do not allow Chinese aircooleds AKA 'cags' AKA cheap ebay bikes.. You must also wear full leather protection..