I've had trouble in the past with police who don't seem interested, we were being plagued to death by local youths a few years ago, and my advice is this. Whether the police want to or not they are there to help! Keep on at them, every time there is a nuisance phone them, call them out, annoy them, and contact your local MP, also contact the local council. We did that and EVENTUALLY it worked! Something was done. I wouldn't advise you to take the law into your own hands cos you'll probably get in trouble! Be persisitant, it does work!