I am not an Aussie, but I did eat at an Outback Steakhouse last night!
Sorry.
In all seriousness I have been on my own for almost 15 years and I first made the leap by securing a contract from a client of my former employer. My employer was ok with it because they were moving in a different direction so the first step out the door was like having a job but I changed status from employee to contractor. The wonderful thing was the customer got me for cheaper than they were paying my employer and I got a big raise. Definition of a 'win-win'.
For most people you are going to have to get out there and do some sales work but what I suggest to people making this leap is to sell yourself to an agency, not individual customers. There are lots of consulting firms who need people and they are afraid to bring on full time work because their variations in work are often from contract to contract. If they land a gig for 4 people and 6 months of work yet only have 3 people they have to spend the time and money to go out and hire someone - then once the gig is done they have to keep that person busy. If they can find someone who will work on the project as a sub-contractor it is much more valuable to them.
Doing sub-contract work like this is a great way to give you steady income while you network and build a portfolio of direct customers where you can make better margins.
Another thing I would advise, realize that your rate represents a perceived value. If I tell you my rate is $40/hr then you think one thing - if I tell you my rate is $195 per hour you freak out, say that is crazy and then think - this guy must be amazing if people pay him that. It changes the mindset and even if you cannot get them signed at 195, it makes 150 sound like a bargain. The catch - you have to be worth it.