Hi Mark
Have you looked at the immigration web-site
Department of Immigration and Citizenship this should answer some of your questions.
Majority of people apply for a skilled independant visa which allows them to become permanent residents and to work and live anywhere in Australia.
As for applying for jobs, my hubby applied for some before we had our visas but didnt have any luck at all. A lot of employers want you to already have a visa and will state this in the job discription.
Once we had our visas though he managed to get a job offer which he starts in Jan but a lot of folks dont manage to secure work until they arrive in Oz.
Have a look at the web-site above, hope it helps a little.
Sam