There are a lot of companion books and spinoffs to the main book so I understand your confusion....there is one for PCOS and one for sports and one for the heart and one for losing weight, one for type 2 diabetes etc.....the main one you should get to start with which covers all the principles of GI andis more generalised is just called the New glucose revolution. no other bits in the title. I have the 2002 (2nd) edition of it....the ISBN for that is -0-7336-1500-7
There is probably a more recent edition though but that should provide a guide to your searching.

Actually I have just found the official wesbite...google glycemicindex and it will come up. Down the left hand side is a tab for GI BOOKS under there you can search by country. America has the third edition..it is the first book that comes up...Aust/NZ appears to have the 2nd edition which is the second book in the listing. Once you have read that one then you may like to branch out into one of the other books more specific to what you are tryingto achieve e.g heart, pcos, etc.....

I am sure Australia would also have the third edition available somewhere considering they are Australian authors and it is australian research or maybe it is just that the third edition was released to yankify it for the American market.....not sure on that one!! GI is quite new to the Americans even though the rest of the world has been following it for about ten years now!!
Oh and with the shoppers guide to Gi values they have just released the 2009 edition I saw it in angus and robertson the other day! hope that all helps Ray!
Happy Hunting!