The Australian customs and immigration services have a strong presence at all international air
and sea ports and they are very strict about visa and entry regulations as well as prohibited
goods. The main Queensland entry airports of Cairns and Brisbane are tightly controlled.They are very efficient at finding restricted goods, particularly illegal drugs - so please don't ruin a backpacking holiday by bringing any recreational drugs with you.
The sorts of things they are most interested in are animal and plant material, food, wildlife, drugs and medicinal products, firearms and currency.
Any products made from animal or plant materials are a big problem. You will be asked to declare all articles of animal or vegetable origin and show them to a customs official. Sometimes, if they are satisfied with the items, customs will allow you to keep them - but mostly the products will be confiscated and destroyed. So best not to bother bringing them, and mostly these products don't fit well into the budget travel ethic anyway.
The reason for this is that Australia is one of very few countries in the world that doesn’t share any of it's borders with neighbouring countries. So we have been able to prevent many of the serious agricultural pests and diseases found in other parts of the world from entering this country, and we are doing our best to keep it that way.
Some states also have fruit and vegetable quarantine checks as you cross interstate borders. Again, this is to ensure that pest-free, agriculturally sensitive areas remain that way. So if you haven't eaten all your fruit and veggies before arriving at the border, they may be confiscated when your vehicle is inspected there.
If you are uncertain what you can or can't bring into the country or across the border, look at the Australian Quarantine Inspection Service web site at www.affa.gov.au.
Apart from these problems, customs in Australia will allow you to bring in just about any article providing that it is for your own personal use and that you will take it out with you when you leave the country. The biggest international airport in Queensland is Brisbane, and as a rule they are far too busy to be concerned to check normal personal effects - however, everything is X-rayed.
Backpacking and budget travel visitors can also take advantage of the duty free allowance of goods (that would otherwise require duty to be paid) of up to the value of $900, maximum $10,000 in cash, 250 cigarettes and 2.25 litres of alcohol.