Res,
I don't know if you know of the Allen Vizzutti trumpet method? There are some thoughts in the front of that about how to cope with performance nerves. He backs up what EC was saying about staying in "realtime" which is important. I think Vizzutti eventually decides that when you find yourself faltering just fall back and concentrate on the air going through the horn. This is what I've always tried to do anyway but somehow I've never quite managed to get over performance nerves completely. I've got a couple of things this thursday (29th) so we'll see how I go!
Stephen