Hi DocOrange - seeing you're in Shepparton, maybe it was the AUSBB Administrator himself you saw modelling the T-shirt!
As for advice, I'd say that you should make your goal to get stronger, and the others will come along with it. Trying to "loose weight" is a negative thing, and hard to stay motivated about.
I'm the same height as you. A couple of years ago I was 79kg, fat around the waist, and had what looked like a 4-month pregnancy.
Now I'm heaps stronger (as objectively measured by what I can lift), three belt-notches slimmer, no longer embarassed to wear a T-shirt (or nothing), and better looking (as indicated by my wife's physical response to me ...). And I weigh 86kg!
Do the "Stronglifts" 5x5 program, or something similar. Weight-lifting is by far the most time-efficient way to get fitter (that's what I think, and I expect most of the other forum participants too - you might get a different opinion on a jogging forum!).
Good luck!