G'day Jen,
Check out
www.darksky.org for heaps of information.
Getting a good ground base of information is probably the best first step.
Once you've armed yourself with relevant info, you're then in a position to know how to plan a campaign (like a good little "dark sky soldier")
Then it's a matter of writing letters, talking to friends, neighbours, local shop owners, posting on non astronomy forums (your blog, as one example)
Dark skies aren't just about astronomy. There are economical and ecological issues involved also and I think that we have to put this multi pronged attack forward.
Evidence is emerging that continuously lighting the night is not good for the mental and physical health of people.
Consider - Life has evolved on this planet which has ALWAYS had a natural division of light and dark. In interfering with this natural cycle we are almost certainly doing ourselves and our environment harm.
Of all the forms of pollution, light pollution is the easiest and simplest to remedy,
if the will exists to do so!
It's our job to actualise that will.
Not trying to sell coal to Newcastle here, just trying to give some basic ideas that you can drop into conversations etc.
Just keep putting the message out however and whenever you can.
Best of luck!