AUSTRALIALoss of the Night app. Be part of a worldwide science project that measure light pollution
Light Pollution on the Astronomical Society of South Australia website - by author.
Adelaide Dark Sky Group a Google forum that includes local issues (link updated 4/10/2012)
Sydney Outdoor Lighting Improvement Society an active group effecting some significant changes to outdoor lighting policies in Sydney.
Astronomical Society of Victoria - Barry Clark's intensive papers on light pollution.
Astronomical society of Australia has a list of Designated Optical Observatories. If you facility has community value getting it designated can help with protecting it from local light pollution.
International Dark Sky Association (US) - extensive resources. Check out their library of educational info sheets
Campaign for dark skies (UK)
Dark Sky Initiative (US) - its author pledges to stamp out bad lighting practices.
Dark Sky - Czech Republic actually have mandatory environmental lighting laws!
Globe at Night - citizen science project to monitor disappearing stars
Starlight Initiative: International conference in 2007 spawns several research papers and declarations for support of dark night skies
And of course Wikipedia's Light Pollution page
Night Sky in the World by Light Pollution Science and Technology Institute in Italy. Deals extensively with light pollution measurements using ground and satellite data. Lots of light pollution maps.
Pierantoni Cinzano's Light Pollution in Italy
Light Pollution Affects Wildlife - Google links. We are only beginning to learn of the disruption that light pollution can inflict on the natural environment.
Light Pollution and Health - issues of lowered immunity and susceptibility to cancers
Night Lights Worsen Smog - Natural night-time break down of smog chemicals inhibited by light pollution
Over illumination can cause health and safety issues - Wikipedia.
Can Lighting Reduce My Crime Problem? (US) - some counter-intuitive findings. From Rutgers University study.
The Sky Quality Meter (US) from Unihedon measure sky brightness. Use it to determine how sky brightness is changing due to light pollution.
SOFTWARE and INTERACTIVES
This on line Light Pollution Simulator illustrates how lighting installations can adversely effect the appearance of the night sky (UK)
Easy Light -Save the Sky (Italy) for the technical minded. Gives you an idea how street lighting is designed.