Usuallee: thanks kindly for your interest!
It's called "Murder on the Rabbit Proof Fence", by Terry Walker. It was published by a specialist publisher in Western Australia, Hesperian Press. It's still in print, as it is scarcely a best seller, and Hesperian do not remainder.
www.hesperianpress.com.
Not yet available as an e-book, although I think maybe I should at least begin to prepare one for when the print copies run out.
A number of B+W pics in the text, and a colour cover photo of the rabbit proof fence near the crime scene, which I took when writing the book.