I have had alot of dealings with Team Drift King motorsport at Aspley. (Not the drift king at geebung).
Dan specialises in mainly intecoolers, exhausts, manifolds, turbo upgrades and the like..
If you need an aftermarket computer tuned I would suggest trying Brisbane Tuning and Turbo, as TDKM and BT&T deal with each other.
Both shops have worked on my R32 when I had it. I highly recommend both shops, it depends exactly what you want as to which shop you take it to.