Welcome to IIS Don.
I used to live at Seven Hills, so wasn't far from you ;-) Had a few friends at Mays Hill too, not far from Parramatta Park either.
If you want some good night skies, and have a car, go out to Jellybean national park. Awesome dark skies, generally quiet. You can camp there as well, there's pit toilets, fireplace, firewood and plenty of room to camp. It wasn't too expensive the last time I was there (10 years ago), $8/night. The road is a bit windy, and dirt and rough in places, but not that hard for a normal sedan. Plenty of bush walking available as well. Plenty of wildlife too, especially the Kangaroos, hundreds of them.
Dave
edit: My bad, it's been so long since I've been there, I got mixed up with the name...It's Blue Mountains National Park, Jellybean pool near Glenbrook. Some links:
http://www.glenbrookbluemountains.co...uct.php?id=242
http://www.wildwalks.com/maps/pdf/nsw-ebmnp-jbp.pdf