Hey mate,
i'm in the bankstown area. I found this place; http://powertune.com.au/ they're close to me, but seems pretty pricey @ $110ph for diagnosis.
A friend of mine encouraged me to get my oil analysed because my oil (motul 300v) changed colour quite quickly ( i dont do many km's in my car ), plus it developed what seems to be a small hesitation at low revs but high throttle... dunno if that's related or not, but he insisted that i should get the oil analysed good thing too i guess.
Anyway, i dropped the motul oil, and filled up with some cheaper stuff to get me by, hopefully i can get a workshop to find the problem without costing big bucks