I'd get in touch with the local Astronomical Society. There will be members there that have access to dark sky sites, as David has said. I've been to plenty of off the side road dark sites and never had a problem with anyone... Most of the time, if they see you they will turn around, because they are looking for a suitable dark site also with no one around. I am now using a property east of Adelaide for most of my observing these days, all fenced in and away from everyone. Only problem, no 240v source
