His profile says he hasn't been online for a few days...if you've contacted him in the last few then that's why there's no response.
He might have gone away, or somethings happened at home, he might have lost access to his computer, it's been a week!!
Have you got an email address, have you tried that instead of PM's?
It's not an ideal situation, granted, but can we not all jump on the vigilante bandwagon of bad sellers please, it does the club and especially the situation no favours at all!!
Emma