I'm not sure about the rules down in Sydney, it comes under the State law of New South Wales, and each state has it's own rules and regulations.
Here in Queensland all contractors must be licsensed by the B.S.A (Building Services Authority) to do work direct to the public. To get around this you an get a job with a larger tiling contractor or smaller contractor with plenty of work. You will have to work for someone in the industry for at least 2 years before you can apply for your contractors license from the B.S.A.
You will also be required to have a very good knowledge of tiling products materials and techniques. Able to fix just about anything and be fast yet neat in your work to make it down here. Employers are pretty tough on slack arse tilers and you will have to proform if you wish to keep your job for any length of time.
On a brighter note though the Federal Government has recently realeased some details on how to attract overseas workers down here, I'm not sure of the details as of yet as they are still in the grey area.
We do have a labour shortage down here at the moment and there is plenty of work to go around.
Here's a useful link If you have not seen it before.
http://britishexpats.com/