How long should I stay here in Australia, without traveling overseas before I get Australian passport?
Residence requirement People who became permanent residents on or after 1 July 2007 must have been lawfully resident in Australia for four years immediately before applying including: 12 months as a permanent resident and absences from Australia of no more than 12 months, including no more than ninety (90) days in the 12 months before applying. People who became permanent residents before 1 July 2007 and apply before 30 June 2010 must have been physically present in Australia as a permanent resident for a total of two years in the five years before applying, including one year in the two years before applying.
You can apply for citizenship (and get a passport) when you have lived in Austalia for 4 years including at least one year as a permanent resident. During that 4 year period, you must had absences from Australia of no more than 12 months, including no more than ninety (90) days in the 12 months before applying. So in other words, now that you have Permanent Residence, you can go overseas for a vacation but if you stay away for 12 months in total during your first 4 years, or if you stay away for more than 90 days in your 4th year, you will have to wait longer before you can apply for citizenship.