Some people don't know where to look for radon test kits. Hence, they don't test their homes. Because radon awareness is such a low priority, most us of don't realize that the kits are even available at the same online spot we buy DVDs and books: Amazon.
Amazon's stock of radon test kits includes:
I'm not sure how good any of these are because I haven't used them, but the important thing is that they're available at the click of a button. It's important to at least be aware of that.