Nikon D800 in stock at Play.com, Amazon.de
UPDATE: That didn't last long, when adding to the basket it says they're 'no longer available'.
Guernsey based dealer play.com has the eagerly-awaited Nikon D800 in stock at £2,599.99 (including free delivery). Please click any of the preceding links to buy or click here to buy (you'll have to follow the links, as there's no direct buy button from the Nikon D800 page).
Download the D800 instruction manual, here.