Salaries can range from $23 to over $60 an hour, are you a new grad or have a couple of years of RN experience?
Nursing shortage is for the experienced nurses. Years ago, hospitals had to meet a new mandated patient to nursing ratio, so hospitals were going on a hiring spree, offering $10,000 signing bonus, visa sponsorship to get more experienced nurses to quickly staff up or the hospital could be fined very heavily or even closed. Times have changed and now we have a 50% unemployment rate for new grad nurses in CA (look up the recent CA BON 2011 survey for the facts) and it's pretty much true for all 49 states.
I don't think you'll find any "agent" to help out and if you do, I would be very cautious about using their services as they will probably charge you $1,000's for something you can do yourself and not able to deliver the moon.
As an Aussie citizen, you will need a SS# to apply into CA. There's a very few states left-over that doesn't require a SS#, as it's actually a federal regulation and not all states have implemented it yet. Some states like NM allows you to take the NCLEX without a SS#, but they will not issue you the actual license until you provide them with a valid SS#. So you really don't have a license to endorse over to any other state. Some try to get their licenses out of state then try to endorse it into CA, but it will not work and will be denied.
Basically, if CA is your final destination, then simply try to get into the CA system, others trying to go thru the backdoor is only finding themselves spending so much $$$ for fees and testings just to find the door is locked as they will not meet the minimum CA BON standards.
Assuming you do get a SS#, you must know that the CA BON has tighten down their educational requirements even with decades of outside nursing experience and must meet the same standards any and all CA students do. I would double check to see if your college courses has the sufficient clinical hours, make sure you have taken the minimum courses required and that you took ALL your courses both clinical and the theory part in the same exact semester, with no gaps. You will find from the International section, those coming in from the Phililpines have all but a handful if that, been denied by the CA BON. It's not only those from there, but from India, UK, Ireland, Russia. It only takes one missing or insufficient item to get the declined letter.