Where to buy a good Buche de Noel?

I'm thinking about purchasing a Buche de Noel for a Christmas dinner. Has anyone purchased one in recent years from a local bakery or know of a bakery that makes them? I'd like a really nice version - with the meringue mushrooms, if possible.

N.B. One such log (I believe, sans mushrooms) was purchased last year at Whole Foods - the type of baked good there that is made outside the premises and is pre-boxed. It was okay- the frosting was a little too "fake" tasting and the cake tasted, well, as if it had been made well-before my purchase date, a la Entenmann's.