This is Lawrence's board, so he's free to establish such a subforum (or not) as he sees fit.
With that said, it's currently my impression that we won't be doing that sort of thing here on GamesX. There are a lot of legal considerations related to sale and trade boards, even without the complications of international shipping and the issues of development kit ownership.
However, if you want to post (in the appropriate forum) about an item you have that's available, as moderator I generally won't have any sort of objection. I'd like to ask that if you do engage in that sort of exchange, be civil and communicate by PM as needed.