I'd have to agree with start small and work your up. I took some mates up to Cessnock from Sydney last June long weekend and was the first time i'd flown friends away somewhere, despite having a fair bit of charter time.
We had an absolute blast, and whilst the airport is a little way out of town, it's not much of a taxi ride. Make the flight a little more intersting as well by heading up the Lane of Entry and continue up the Central Coast. The proximity to Bankstown probably means you won't have to refuel either, but if you do, i'm pretty sure there is a bowser. Get an instructor to take you to the self serve bowser wherever u train and run through the procedure (although IMHO this should have been part of your PPL training).
Cessnock turned out to be great, especially a great Irish pub out in the vineyards called Harrigans. In the area there is plenty of accom to choose from, vineyards aplenty and believe it or not, plenty of skirt to chase. Lots of p1ssed Sydney girls on weekends away looking to misbehave (or so i've heard
).
Cheers,
TL