Manxie - I don't recall any discussion of this amongst the admin team. We do sometimes have pretty full PM boxes so it is possible that PMs get missed every so often. You are certainly not being "ignored".
However, the admin team are here to run the forum. That is the extent of the "shebang". If members who have been put into contact by the forum decide to trade then, as indicated in the guidelines, they should satisfy themselves that they are happy to trade with each other.
The admin team have implemented a post count threshold that must be reached before posting in the trading sections and also publish a list of conflicts in the trading sections to minimise rogue traders and assist members in deciding whether they are happy to trade with each other. However, once two parties have entered into a transaction we can only really suggest that they contact each other to discuss a resolution. If you phone in response to a classified ad in a newspaper what help would you get from BT or the newspaper (who provide the communication medium - just like OOF) if it went wrong?
Please PM a member of the admin team if you wish to raise a dispute.
Kevin