Missing is a terrible feeling. I hope you find him soon.

Do you have any flyers up? Put the word Reward on the posters in huge letters. People are sometimes more willing to help for a little cash. I'd put them wherever kids in your neighborhood hang out. Kids cover a lot of ground in the summer and see a lot of things. They may spot your pupper. Call every vet clinic anywhere near you. If he's been hurt, someone may drop him off at a clinic. Check the shelters and animal control, in person if you can. Busy shelter staff may not know they have your dog by your description.

Good luck. We will keep all paws crossed!