My city (low density suburb of Los Angeles) has outdoor lighting ordinances that spell out rules: all outdoor lighting must point downward, street lights are not allowed, holiday lights must be removed a week after New Years. There are also ordinances governing disputes--fees to get the inspector out at night, paperwork, etc.

If you want dark skies, take some friends to a city council meeting and make your case for similar ordinances. It's doable, even in a place like Los Angeles.