Hi Mike,

, &

to IIS!
I'm sorry to answer your question with another question, but will you be driving, and will you be bringing any astro gear?
You can also drop a line to the various astro clubs listed here in IIS (I've added a link to the page). They will have dark sites that are regularly visited, some closer to Sydney than others. Some of the more remote sites being about 3 hrs drive from Sydney:
http://www.iceinspace.com.au/clublistings.html
If you are feeling adventourous and are driving, and with an asto theme in mind, you might like to visit Parkes Radio Observatory,
http://www.parkes.atnf.csiro.au/
or the Siding Springs Observatory at Coonabarrabran:
http://www.mso.anu.edu.au/info/sso/
Here are some other astro places of interest:
http://www.quasarastronomy.com.au/places.htm
The Star Parties forum also contains info regarding get togethers across the Country, including those organised by IIS members. The Sydney based ones occurr at "The Pony Club" at Mangrove Mountain (to the north) & "Katoomba Airfield" in the Blue Mountians (to the west).
Mental.