Assuming you have the person's full name, your best option is the various Veterans and Military Associations around the country, most of which have web access. A good place to start is Military.com - myself, like many Vets, are registered there under the units we served with. Knowing where your friend served (ship, shore installation, Vietnam, etc.) will make it much easier for you to locate him. If you already know where he was stationed or what command he was assigned to, Google it and you'll likely find a Veterans group associated with it, which is a great place to start.
Reunion sites are a good resource as well - Classmates.com has school, business and military groups associated on their site. You can join most without a fee, though with limited contact capability. Still, it allows you to at least see if the person in question is even signed up to that site if you want to go further.
Facebook isn't a bad place either - I have friends who are getting contacted from people they haven't heard from since they were kids who have found them on FB.
Coast Guard Foundation was created in 1969.
Fife Coast Railway ended in 1969.
Gulf Coast League Nationals was created in 1969.
Gulf Coast League Expos was created in 1969.
Seaboard Coast Line Industries was created in 1969.
My Friend Tony - 1969 Molly 1-11 was released on: USA: 18 May 1969
My Friend Tony - 1969 Encounter 1-7 was released on: USA: 23 February 1969
My Friend Tony - 1969 Casino 1-13 was released on: USA: 1 June 1969
My Friend Tony - 1969 The Hazing 1-6 was released on: USA: 16 February 1969
My Friend Tony - 1969 Kidnap 1-14 was released on: USA: 8 June 1969
The cast of The Good Friend - 1969 includes: Pat Carroll Paul Frees
My Friend Tony - 1969 The Lost Hours 1-5 was released on: USA: 2 February 1969