Usually a cat which is a pet of somebody always returns at the time of food, but if in your case the cat is not returning even at the time of its food, it is certainly in some problem. And to find it you will have to keep your cool and prepare the strategy to get it back.
The first step you can take is to contact your neighbours as it might be possible that some kids are in the neighbouring house and the cat is playing with them and they also have provided food for it. But even after a day or two, if your cat does not return then certainly you will have to take some steps.
You can contact local animal care centres and simultaneously publicise the photo graph in the local newspaper. You can also stick posters of it in the nearby areas so that if somebody sees the cat, he can inform you.
After taking all theses steps you can hope for the best.