1) Internet search for a camera shutter file. You can trim this if it's a little long using the .wav editor
http://www.freesound.org/people/Nathan_Lomeli/sounds/79190/
2) shutter.wav .
3) .h
@interface myViewController : UIViewController {
SystemSoundID SoundID;
}
4) View "viewDidLoad":
NSURL *buttonURL = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"shutter" ofType:@"wav"]];
AudioServicesCreateSystemSoundID((__bridge CFURLRef)buttonURL, &SoundID);
5) button_click:
//play then shutter.wav sound
AudioServicesPlaySystemSound(SoundID);