I understand your frustration, and I feel bad as I was the one to vouch for RJM (if you are there RJM get this resolved as it is reflecting badly on me too), but I think you could give it a little more time. His lack of communication is not helping and a simple message saying he got held up or couldn't get to the PO etc would go a long way.
As for whether this happens on the forums a lot, I don't know. But I think it is always safer to trade on a dedicated trading platform such as Bartertown or even ebay as they will go to lengths to ensure things are done fairly. If someone commits fraud (I am not saying this is, yet) on Bartertown the mods over there will get their address and track them down.
I will try to contact Ryan through BT to see if he will come over here and let us know what is going on.