You might try the Family Tracing Service offered by the Salvation Army:

The Salvation Army Missing Persons program is a unique international social service. Its purpose is to help facilitate successful reunions between family members who have lost contact with each other.

Searches are conducted utilizing a variety of methods, including government offices, credit institutions, social service agencies and law-enforcement personnel. The Salvation Army is instrumental in re-uniting thousands of families each year. The Missing Persons office receives an average of 2,000 inquiries; opens approximately 600 new cases and locates an average of 350 people annually.

http://www.salvationarmyusa.org/usn/www_usn_2.nsf/vw-dynamic...