Alatron,
Not to contradict Steve too much but, one tower course recently of 3 each got exactly where they wanted... 1 of mine did and from what I recall pretty much at least 1 from each course while I was at the academy got where they preferred.
This being said, you are agreeing to go wherever Airservices prefer when you accept their offer of employment.
There are many hurdles in your way before you have to worry too much about it. Working in Adelaide could be more of a long term plan rather than settting out for it initially,
Good Luck!
Spanks