From the previous link of:
http://travel.state.gov/passport/get/Secondary Evidence/Secondary Evidence_4315.html
This what you need to do:
Go to your STATE Office of Vital Records - or equivalent for your state. Have them do a search for your father's birth certificate.
When that search comes up empty - have them issue a "State Issued Letter of No Record" It must contain his name, his date of birth, the years time frame for which the birth certificate was searched and an acknowledgment by the state that no birth certificate was found.
This Letter MUST be presented WITH a combination of any following records:
# Baptismal certificate
# Hospital birth certificate
# Census record - (You can search the 1930 census for free at your public library OR through
www.heritagequestonline.com if you have a library card) If you have trouble finding him, I will be glad to help you, I am a big genealogy buff - PM me if you want.)
# Early school record
# Family bible record
# Doctor's record of post-natal care
- Basically it means ANYTHING that a second party would have written that mentions your father in the time frame of his youth.
But the key to this is State Letter of No Record - without that, you can't get the passport.
Take these records to the Passport Office along with a print out of the above mentioned link, so you know where you stand - Then he should be able to get his passport.
Good Luck.