I’ve just noticed, RS Components are selling Arduino boards, shields and books.
I use RS because I live near a trade counter, and can get parts within two hours. So, for folks who want an Arduino now, maybe you can!
(I am not on commission, and have no business relationship with RS, other than giving them money for components :-)).
I still recommend buying Freeduino’s from Nuelectronics, they are significantly less money.