For what it's worth I've had another think about how I could use a website to list customers who haven't paid and the only way I could think is to be too open with it all. Perhaps by listing the full details of the job, the agreed quote (signed where possible), the time quoted, the time it took, the suppliers involved/used costings and everything and then give the customer a chance to respond etc
But. I think it could make the right guy look wrong and go against your reputation a bit. And it could bring your contacts / suppliers into it too etc
Not sure that's the win:win type of website that I like to setup. So back to the drawing board.