They also have a cool video showing the process of building the rig. Killing the rig. And rebuilding a better rig. The video has been around for some time, so you might have seen it before. I managed to miss it, so if you haven’t seen it yet, it’s definitely worth 6 minutes of your time.
Some more resources for the “groundly challenged”:
If kite aerial photography is your thing, check out the KAP flickr group obsessed with hooking kites with cameras.
If hooking your camera to an unstable-ground-hitting device looks like fun to you, check out Scott Haefner Blog and image gallery. This guy knows what he is doing.