I found this on the SNA site:

Filming

John Wayne Airport welcomes film, television and photography projects.

Permit fees are $400 per day for motion picture and video productions.

Permit fees are $150 per day for still photography.

Permit fees are waived for non-profit projects, with proof of non-profit status.

Security deposits, insurance and some costs for staff time are also required.

http://www.ocair.com/tours_and_filming.htm

If i take my camera and shoot from the terminal, do i need this permit and will I be hassled if I don't have it?

Thanks,
Steve