I am very grateful to the thegreatambler.com for making available GPS data files.
All I have done is download their GPS files and converted them to .kmz for use with Google Maps / Google Earth and added the two campsites.
You can download the .kmz files and open in Google Earth.
Camp Day 1 (unofficial)
Camp Day 3 Joan Point (unofficial)
Forest Campsite (unofficial)
Port Davey Track
I also found the following sites very useful, so many thanks to the authors;
http://ourhikingblog.com.au/2008/07/port-davey-track-trip-report.html
http://www.traveller.com.au/south-by-southwest-pimv
http://www.gregspurgin.com/tasmania/walking-the-port-davey-track.htm