hiya
welcome aboard...
I am from campbelltown and while my skies arent super dark they are dark enough to make out the helix nebula in my 8" f6 reflector. following the hume highway about 1 hour west and you get some really dark skies around belangalo forrest (milat country) and 1/2 an hour from my place is The Oaks which is pretty dark too but there is a litle sky glow towards sydney.
thats sydneys south west tho, not north west where you are talking about.