gimmie your account names and passwords I'll do it for you Pitbull and I promis I will not take your golds and will not make sex leg posts on the wow forums... Well maybe just a little golds and a couple forum posts
When I logged in now there is a section right up top "Link a World of Warcraft account"
And then a little down there is a section that says "Add a Game"
When you use "Add a game" it asks for the CD key. But if you use the "Add a Wold of Warcraft account" it just asks for your account name and password.
So for WoW just use the extreme top one and not the Add game menu