Hey guys, not sure how many of you are aware of this, but I am pretty sure that you CANNOT legally sell a CD key for a game. A typical EULA (End-User-Licensing-Agreement) will prohibit this kind of activity. Unless you are a certified reseller, and can provide credentials to this, then please do NOT post sale ads for CD-keys on the forums.
You can sell the game, and then accidentally ship them the CD key with it, but that's all that will be done here.
-Modgers