Don Shipley, a retired Navy Seal, has developed a cottage industry of exposing fake Navy Seals. For years he did this for free, but the volume of inquiries has forced him to charge a $20 fee for the service. Give him the man's first and last name and approximate age and he will give you a report.
Get the information at
PHONY NAVY SEALs Verifications | Extreme SEAL Experience .
Shipley can also be seen on youtube videos.