If you live inside City limits be sure to check those places first! Then I would put up flyers up (Vets Offices)and drive around everywhere looking and calling his name. I'd even call the police non-emergency number asking if any reports of maybe someone found him and trying to find owner. Look in paper and place ad lost & found. I know you are panicking these are just a few suggestions. I'm going to start micro chipping my dogs. Good luck and I so hope you find your boy soon.