Hi smc
Get in contact with your dealer they can retro fit one for approx £150. We had one retro fitted in my wifes Fiesta Zetec S before she got the Kuga. The kit cosisted of a key operated switch in the glove box and a warningicon that illuminates when you have the airbag switched off. The warning icon is located on your switch panel in one of the spare spaces.
I couldn't believe that Ford don't fit this as standard, as most other manufacturers do.
Regards
Kugameister