Hi Eire2011
I am in a similar situation to yourself (Irish physio heading to Australia May 2011 all going well) and I've found some other entries on the forum quite useful. In particular the entry re: Limited registration if you wanted to look at that. I've decided to use this type of registration to allow me to work. Check out the APC website at Forms — and click the link for application form for limited registration in the public interest. For this type of reg you do need to secure a job offer but then full reg requires you do theory and practical exams which for the relatively short time you want to work in Australia really isn't worth it. That's how I see it anyhow.
A working holiday visa (subclass 417) should be the visa appropriate for you if you intend to stay 12 months or less. You can read about the specific conditions of it on the Aus immigration website Department of Immigration & Citizenship
Registering in NZ also an option but there is a declaration in the application to say that you are seeking employment in NZ. There are some other entries on the forum that discuss this if you have a look.
Hope some of this helps. Would be great to know how you get on or maybe you'll find out some other useful info in your info searching...it's not easy!!
Aoife