There are actually free videos online showing the frog and helo, but I have a DIR DVD that shows them as well.
From my own experience, if one knows the basic frog kick, and only kicks that way for long periods of time (like a shore dive, and many of them), eventually you'll get better and better at making it faster and more efficient. I noticed that, sometimes when keeping up with relatively fast flutter-kickers, I would get into a really efficient rhythm and mid-torso movement that, while it worked really well, would have been near impossible to garner from a video or learn from someone else. it was just something that had to evolve.
The helicopter, on the other hand, was something I needed to see once on a video to understand it was basically the foot on the side of the direction wanted that did 90% of the work. Easy as pie once you see it from a video and realize what the diver is doing, and what they aren't.