I ordered it from Dixons a few days ago but have had such trouble getting one I wasn't going to believe it was ours till it arrived!
I think the only reason I got one was because I had put all my details into the Dixons site the previous day, but by the time I got to the end of that process they were already sold out.
This seems to be the way to do it. Register first and then wait for the wii locator to pop up with where they are instock. This means you effectively jump the queue if you don't have to input details. Oh and if you have an Amazon account keep that open too.
Good luck