Currys, PC World, Dixons (The Dixons Group in general), infact most British high street stores are several weeks behind in getting new items instock, unlike the American stores who get that within a few days after the Apple Store gets them.
The only exception is
http://www.anvika.com>Micro Anvika who think they are the Apple Store, but do stock Apple products pretty quickly.
They have stores in London, Manchester, Birmingham and Croydon. Yes, i also wonder why Croydon...
*nathan