The Social Security Administration will forward letters to persons active within its data base. This base includes all current Social Security beneficiaries, Supplemental Security Income recipients and those working and paying FICA taxes on wages (letters would be sent c/o of the last employer of record). They will not forward pictures, keepsakes, etc. and will review the letter for appropriateness, e.g., no requests for money, etc. The person's SSN is required to locate the person. However, identifying information, particularly the mother's maiden surname, state/country of birth, and date of birth (at least the year) will generally allow SSA to derive the SSN. Under most circumstances they will advise if the person is deceased. If a state electronic interface is the source of death information, state law may restrict disclosure of the death. There is no form and to my knowledge no cost. It is advisable to present the letter in an unsealed envelope in person to a local office.