The Australian Immigration and Multicultural Affairs website . All correspondence must be by mail. Being employed on a graduate program doesn't count as experience.
Some occupations get prefferential treatment.
If you have a criminal record there's probably not much point applying. Should you get past all this, you get a visa stamped in your passport that is both for migration in the next year and multiple-entry for the next 4 years. It will be very unlikely that you will be able to work.