A search would answer most of these questions.
Any way, I'm in a good mood.
You can work in Australia if you have the correct visa. If you do, then the only barrier to getting a job is yourself.
Regarding the licence recognition, PPL no problem, any thing else requires a conversion. Going from a CASA lic to a JAA/EASA lic equals repeating all 14 ATPL exams and doing a fair bit of flying, more so if you don't have an instrument rating.
More about it in LASORS on the CAA's site.