In case you are looking for it too, here are some things I found.

Daryl is right, I did find it at Sears. I went to the part where they sell washing machines and other appliances, and it was nowhere to be found on the shelves. I asked a sales person, and she had never heard of it - but she was very nice, and went into the back room to search through boxes. And to the surprise of both of us - she found it! I had expected it to be a jar with some kind of brand name on it and the ingredients listed in fine print on the back, but there it was clear as day on the package: "Kenmore Potassium Permanganate - For use to regenerate manual iron removal filters." It was a small plastic jar, so I did not have to buy a large quantity.

I had gone to the LFS, and a sales person there who really keeps fish (and who knew what PP was, and had some at home) told me that they did not carry PP because one needs special licensing for it. Maybe that's why Sears did not have it on the shelf, per licensing requirements?

The LFS person recommended that I try http://www.chemistrystore.com/potassium_permanganate.htm . It is available there in larger quantities than the little jar I found. You have to fill out a "Hazmat Waiver Form" that you sign, and mail or fax in. I suspect they do that with a lot of their products, given the nature of their business.

I also read about a product called "Jungle Pond Oxy Clear" which says that it contains Potassium Permanganate, too. I am curious if anybody has tried that product.

Now I have to figure out how to use this stuff.

I couldn't find it in stores in the neighbourhood so I' buy it at the apothecary. I think because the licensing polecy in Belgium is different than in the USA. The stuff is cheap at the apothecary also

first off get a gram scale. Especially using in tanks it would be VERY easy to overdose using the teaspoon method. This stuff is nasty, an oxidizer..Think powdered chlorine..nasty stuff. So use with care. It WILL stain your skin brown if you get it on your skin That is of course from experience!

I have actually found and bought PP on ebay..go figure lol

You can get it at Homebrew supply stores too.

Yes, this is how I got my pound of it. Let me just say there is no way I will ever use up this pound! I don't use PP in the tanks, just as a disinfectant and as part of the quarantine procedure if need be.

You can often measure it by the color of the water you have. Though if you are using it for fish I would recomend that you do buy a scale which measures grams. Not sure you'll ever need a gram even! Unless you're treating some huge amount of water then it is just keeping the pp:water small, at say a gallon or two. [:

Great info, here!
If you go to that website they do explain a lot and give a great idea on the stocking solution!

I havent found any at my local Sears nor anywhere else... petshops, not even the Pond/Aquarium Specialists had any. Does anyone know where I could order some online for Canada?

I just discovered Permoxyn, a potassium permanganate product, on Goldfish Connnection. My order arrived over the weekend. I've already soaked several bunches of new Anacharis in it. It was really simple to use. I guess I'll find out in a week or two if it actually killed all the hitch hiker snails without harming the plants.