Geoff is associated with the AHSA (Aviation Historical Society of Australia) and Aviation Museums such as SAAM in South Aust and QAM in Queensland, but I would assume the contact button on his website would be the quickest way to locate him?

http://www.warbirdsdirectory.goodall.com.au/

If that is unsuccessful, those other organisations he is associated with can be contacted via their own websites

http://www.ahsa.org.au/

http://www.saam.org.au/

http://www.qam.com.au/

Regards

Mark Pilkington