Hi there!
If you choose to drive from Cairns to Brisbane, be aware it is a long trip. 2713km (1696 miles) & 37 hours - going from Cairns to Brisbane down the Bruce Hwy, then from Brisbane down to Sydney on the New England Hwy. That isn't allowing for you stopping to sleep or look around (the driver misses a lot of the scenery don't forget!). So you could expect to do it much more comfortably breaking the trip into 3 or 4 segments.
Yes, the scenery is pretty. Driving is a good way to see the range of Australian scenery and you will get the range from tropical up at Cairns to the New England tablelands in New South Wales.
Invest in a good touring atlas of Australia before driving anywhere - they have all the main roads plus the smaller roads which might be more picturesque for you both.
Flying is much more time economical however and there are some good cheap flights available. If you get a cheap enough flight, it might be cheaper than driving (rental plus fuel plus accommodation plus food). Just depends how long you have over here. Look at
www.virginblue.com.au or wwwjetstar.com.au for cheaper flights. QANTAS (
www.qantas.com.au) even has good specials sometimes.
The Da Vinci syrups are available in Sydney from Pine Tea & Coffee (Unit 17/ 8 Gladstone Rd Castle Hill 2154 ph: 02 9680 9117).
Sorry can't help with other product in Cairns or Sydney, I live in Brisbane. I will have a dig around for what is available here. I know a list of what is available where has been posted previously on this forum.
Hope this has helped!
cheers
Rosemary