I think that you need to have a neighborhood block party. Don't mention anything about dogs at all in the invite. In the process of organizing etc, people will 'see' themselves a bit clearer and not be so defensive.
You may need to start small like this:
You take a small tray of something wonderful and taped to the bottom is 10 addresses. You give it to one of your neighbors with the instructions to put a treat on it and pass it on. That's pretty non - threatening. Then maybe move on to a neighborhood gathering of sorts.
Maybe a "TELL US ABOUT YOUR DOG' neighborhood chain letter. Anything to connect has got to be worth the effort before you go the 'reporting to the authorities.
We are all too disconnected and these dog things then get way out of hand and while we all try to do the right thing - complaining about other peoples dogs just reinforces the steriotype of dogs are trouble. We used to be able to work things out with each other but no one seems to take the time anymore.
For those of you who are old enough, "if you aren't part of the solution you are part of the problem." (If you're not old enough to have heard that before… ask your mom or dad )
Let me know if you try any of these ideas - I've done this in my neighborhood before - the only problem now is that if there is a stray - people bring them to me cause they figure I know who the dog is since I'm the 'dog lady'.