First check the connections of his close friends. To go nowhere teenagers are usually afraid. The easiest way to find them from friends or relatives. If friends of his son's age, they may not issue the place the presence of your child, then you should contact their parents. To ignore this gesture is just not worth it.
Examine the contacts of the boy on social networks. In General, psychologists do not recommend to climb in correspondence of Chad with peers. But in critical situations it is permissible. Visit the child on a social network you can find potential like-minded people in whose company he spends time.
Hire a detective if you care son repeated often, and each time you are unable to find it on their own. This is absolutely an extreme case, and to resort to it is only in difficult situations. It is important to ensure that the child spends time not in crack dens, not on the training sects and not bad. Just don't tell him about this step, otherwise you risk losing trust.
Work on psychological climate in the family. Apart from purely organizational measures to search for a missing child, it is important to eradicate the roots of the problem. Teenagers leave home only if the parents are wrong to react to the crisis of development in adolescence. This crisis is manifested in the fact that the teenager wants to be treated as an adult, but he has no resources of its own for independent living. The best method of response by parents on the crisis of adolescence is to accept growing up son. And help in finding resources to become more independent. Continuing to live with their parents, the boy himself can make, for example, computer games or gadgets. Just give the money and continue to control every step the child is not the solution.
If you want to avoid quarrels and protests from the son, stop trying to pressure him. Take seriously his opinions, decisions. Quietly and unobtrusively, on the rights of older friend show the pros and cons of each solution. Instead of a monologue and pressure continue to dialogue and discussion. Realizing that his value as a person, the child will never leave your home. At least, until I finally grow up.