I hope it is not too late to anwer you this question.
I brought two doggies to Sydney from Hong Kong in February.
I will PM the name of my agent to you.
Remember, you have to start all the procedures at least 5 months before your emigration date. I am not sure if the procesures of cat is the same as dog. For my dogs, they have 3 blood test in month 1, month 5.
If you are going to Australia, I would not suggest you to do it yourself if you have a full time job.... If you miss one single paper you will be in big trouble in getting your pet here.
The total cost for me to bring two dogs here was about HK$30,000. (using the excahnge rate of last year).Cat may be slightly cheaper...
where are you staying? sydney?
there is only few quarantine centre in australia, I know there is one in Sydney. for more information you can go to website of AQIS http://www.daff.gov.au/aqis/cat-dogs