There's also a bottle put out by Sonne, Perfect 7, and I think Dr. Bernard Jensen himself put out a bottle. Great stuff, all. :)
Check your local health food store and see if they sell psyllium in bulk - it's cheapest that way.
You can also buy an intestinal cleanser that already has clay and psyllium, but be careful, many of them also have laxatives such as cascarda or senna which is not great over time.