It was on Friday Night with Jonathan Ross. It was just Wossy showing a couple of sackboy plush toys in the likeness of himself and Ricky Gervais. The LBP part is really short (like, a two minutes long), but the episode's worth checking out just for how funny it is.
If you're in Britain, you can check it out on the BBC iPlayer now. Non-Brits will have to wait for someone to upload it onto youtube, I guess.