I just video taped my swim using a friends video camera. A friend shot video from virtualy every angle (except underwater, which is super cool if you have access to that kind of set-up).
Needless to say, what I gleaned from watching the video tape is amazing. Little things like hand angle entry, leg splay, rotation and the list goes on.
If you have never done this. Do so. You’ll be amazed at what you see. 
(I realize that many camps and coaches use this technique, but you can do it yourself easily and inexpensively. And, it only takes a few minutes to capture the shots you need. While your at it, have your friend shoot your run stride and bike as well!)