If you have a homeowners group/association (some residential developments have them to enforce strict maintnance codes and petty things like no political signs on your lawns) for your development, check them out and ask them for help.
Otherwise, check out to see if your county or city has any resources available for mediation or tenant/neighbor relations (a google search brought up
http://www.landlordtenantinfo.org/ and
http://www.hcd.ca.gov/
(Some landlords may be willing to mediate before court although it sounds like in this case, they don't care, even if you hand them a subpoena).
At the same time, don't forget to be nice and considerate to the neighbors, not only because it's the right thing to do, they may interpret you and your neighbors' behavior as trying to get them evicted because of prejudice and discrimination
(and in today's america, even take you to court because of that)
Good luck with it and let us know how it goes.
Catcha back on the flipside,
keyshawn