The cache is not at the listed coordinates but is close by.
To solve this puzzle you simply need to use clues on this page to visit a website where the co-ordinates will be revealed. The website is a straight html file, completely safe with no gimmicks or anything that will harm your computer... go to http://www.gc?????.??
The starting co-ordinates are the closest thing to a 'beach' in Rockhampton - why don't you visit it and check it out. Watch out for 4 legged reptiles that bite... and when retrieving the cache be careful for muggles with fishing lines.