The biggest challenge will be getting your first
HR job. This is never easy because most employers tend to prefer people with some relevant experience, that said we have seen a few more graduate opportunities come up recently.
The prospects are certainly better than they were 12 months ago, but the
HR job market is still in recovery mode and a long way from where is was in mid 2008.
We have also seen some discussions on this forum about how hard it is for recent immigrants to get a
HR job and I suspect there is a tendency to favour people who have Australian qualifications. This bias may not be warranted, but I am sure it exists. Your communication skills will also be very important.
To some extent your chances will be dependent on your determination and flexibility. For example it may be easier to get a job in a regional location rather than one of the main cities, because there is less competition.
Another thing you need to carefully consider is that your chances of securing a job
before you are here in Australia, with an appropriate work visa, are just about non existent and no employer is likely to be able or willing to sponsor you for immigration purposes for an entry level position (they will be required to test the local market first).
So you would need to apply for permanent residency on your own merits. This is relatively straightforward if you are below a certain age and have appropriate qualifications (which you do), and are in good health. However, it is not a cheap process and you would also need to be able to support yourself once you get here until you secure a job.
You can find out more about the immigration aspect here
Department of Immigration & Citizenship
This may all seem quite negative, but I feel it is important to be realistic, because many people have come to Australia, spending a significant amount of money in the process (sometimes their life savings), only to find they cannot get a job in their chosen profession.