Thanks for the ideas (and sorry to have derailed the thread!)
I have DIving Australia already, you're right some great suggestions, unfortuantely everywhere sounds great and I only have 6 weeks!
I totally agree with not just doing the GBR, I only have a week there (mainly cos I can't go all that way and NOT do it!) So am going from GBR to Sydney, the Melbourne, Adelaide (cos I met someone who runs a shop[ there who'll give me tanks and a map and let me get on with the camera thing), up to Ningaloo and then a couple of weeks driving back down to perth sampling the diving along the way...
So couple of definites, Sydney Harbour and down to Jervis Bay for a day...
Thanks again all 