If you are in Hobart area I really recommend GT Garage on Lampton ave Derwent Park. Really really nice guys, good service, honest, and best of all they take the time to really talk to you and find out what you want and explain exactly how/what they will do and what effect it will have. I have had really great experiences dealing with them.
http://www.hobartdynotracktuning.com.au/home/
Cheers