Good timing on the post there...
The Canberra Aero Club does not have 'airside access'. In the last few months, Canberra Airport created an 'access facility' for GA. You can get out, but you can't get in (you have to call the duty person to let you in). Which means you would need someone to escort you back to your plane when you leave (and if you want to be legal about it, have someone escort you from your plane to the gate when you arrive). If you PM me, I can send an email around to some members (I'm on the board) to see if anyone can help you out (I would - but I'll actually be in Melbourne for the long weekend!!)