A link off the homepage, straight to a .co.uk GCheckout page:

http://www.google.co.uk/checkout/backtoschool.html

Strange. Possible UK version?

Images: http://picasaweb.google.com/thomasdavies/Google/photo?authkey=PFNycsmvrIafb2ORfm7cUhzukCo#4963554265317441554

http://picasaweb.google.com/thomasdavies/Google/photo?authkey=PFNycsmvrIafb2ORfm7cUhzukCo#4963554267830616082

It is strange that it is a .co.uk link, but still with $ pricing.

Not as strange as you might expect I don't think. The prices are all in dollars.

http://www.google.fr/checkout/backtoschool.html
http://www.google.de/checkout/backtoschool.html
http://www.google.es/checkout/backtoschool.html
http://www.google.it/checkout/backtoschool.html

It works on them all.

Ah rite ok then :P, but why the local domains?

I don't know. A lot of stuff works on any Google domain. I am not sure why they do it.