Yes, it seems barbaric that this treatment isn't available to the hundreds of millions of sufferers worldwide. Even in the US, where there is growing number of ketamine clinics, most doctors have never heard of ketamine treatment for depression, and those who have are very wary of offering it. Many of the leading US researchers actively discourage its clinical use. These attitudes are partly a result of ignorance, and also a reluctance to embrace the radical new pathophysiological model of depression that ketamine research has revealed. But the most common objection to using ketamine is "We haven't finished studying the long-term safety of repeated ketamine use." But I'm more interested in the consequences of NOT using ketamine: over a million suicides per year worldwide, and 350M living lives of misery that can hardly be called "living" at all.
I don't know much about the Australian medical community, but I have come across a few things over the last couple years that might be useful to you...
Colleen Loo, a psychiatric professor in NSW is conducting research on ketamine for depression. See
http://www.blackdoginstitute.org.au/public/research/meetourresearchers/colleenloo.cfm. Perhaps it might be possible for you to volunteer for a clinical trial? Or perhaps she might know of other ketamine studies in Australia that are close to you?
The Royal Flying Doctor Service uses ketamine to sedate patients for transportation. If any doctors in Australia might be willing to consider treating depression patients with ketamine, it will be those who have experience administering the drug and who understand just how safe and harmless it is when used in a supervised medical setting. Perhaps you might get some leads by tracking down a few RFDS doctors (or former ones) and asking them if they know any colleagues who might be willing to consider offering ketamine infusions? Here's one such doctor:
http://www.smacc.net.au/committee/assistant-professor-minh-le-cong
Of course, anesthesiologists have far and away the most experience with ketamine, and they understand its outstanding safety profile. In the US, the doctors who offer ketamine infusions are nearly all anesthesiologists for this reason. Perhaps you could track down some anesthesiologists near you and ask if they know of colleagues who might be willing to offer infusions for depression?
In the US and a few other countries (not sure about Australia) ketamine is also widely used in pain management. Certain types of neuropathic pain, including a truly horrible condition called CRPS/RDS, respond to virtually no drugs besides ketamine. In the US, many of these pain doctors (or "pdocs") already perform ketamine infusions regularly for CRPS/RDS patients. Since they already have the experience and infrastructure, some of them now offer the treatment for depression patients, too. Again, it might be worth tracking down some local pdocs to ask if they know any colleagues who might consider this treatment.
Finally, if you ever have reason to travel to NZ, there is at least one doctor who is treating depression patients with ketamine:
http://www.otago.ac.nz/dsm/people/expertise/profile/index.html?id=821. Just like his counterparts in the US, he ran into resistance, and even had to defend himself against a regulatory inquiry:
http://www.odt.co.nz/news/dunedin/280719/wary-psychiatrists-avoiding-label-use-ketamine. I hope it has not caused him to stop offering the treatment.