Hi starfire. I will do my best to answer what I can.
I think this is going to take some more planning on your part. I assume you are going to apply outland via the Sydney visa office. The entire application (sponsorship and PR) are first sent to Mississauga for sponsorship approval. In sponsoring your family, you are agreeing to be responsible for them for 3 years, meaning they won't go on any public assistance. In order to be approved as a sponsor, you have to prove that you can support them financially, ie provide them with financial statements, tax returns and proof of employment. Basically unless you are super wealthy, you are going to need a job before you apply.
If your husband is under 30, I believe he can apply for a work visa under the international experience class. Otherwise, he can enter Canada as a visitor for 6 months. As a visitor he cannot work. If he enters as a visitor, Canada immigration won't be happy to see a one way ticket. If you have to have an interview (which I doubt you would after 7.5 years of marriage), the interview would be held in Sydney, another reason to have a return ticket. Your husband's visitor's record can be extended at the end of 6 months.
I believe your baby (if born after April 2009) may be eligible for Canadian citizenship by virtue of you being a Canadian citizen.
I think you should wait to apply until you are back in Canada with a job and a residence, it will be so much easier.