Only thing I could add here is try leaving some of his favorite food outside where he can come get it.
Also, am I assuming correctly you've tried driving or walking around the neighborhood and calling him? He's probabaly scared, so if you try it in the evening when there's less activity, he would probably recognize your voice and come out of higing
I had a cat that disappeared for a week and ended up at someone's house about 10 blocks away, mewing and pushing her paw through the mail slot to get someone's attention! She had a collar, so the people could call us. So if your cat doesn't have a collar or microchip, be sure to post those photos around and a description in the paper, both with your phone number, so whomever finds him can gfet in touch with you.
Please keep us posted.
