Hmmmmmm, whilst your idea might be in jest, I think one could seriously do something with this idea. Not a knucklesgroup but more like a pressuregroup or something. I.e. have a few people in each country who are willing to write a letter, give possible scammers a call and perhaps even pay them a visit and politely ask what the deal is with non arriving items.
(The main idea being that it might make more impact when someone nearer the perpetrator contacts him/her).