if this is any help to anyone I've posted an overview of harmonics and their techniques

http://www.guitartricks.com/2000/trick.php?trick_id=5647

What I can add to this is that if you want a really bloodcurdling metallic wail try getting two pinch harmonics on adjacent strings and bending the lower one up to the pitch of the higher one and back down whillst making a vibrato with the whammy bar and exaggerating the ringing with a trebly wah effect. It's hard to do this particular type but bear in mind that any bend out of phase with two or more pinches sounds cool. Satch does this sort of thing on Crushing day (one of my faves!).