Where can I download Natasha Bedingfield "Pocket Full of Sunshine"--it was on the Hills Season 3 Finale?

Where can I download that song that was on the Hills Season 3 Finale last night (December 10th). I think it was Natasha Bedingfield Pocket Full of Sunshine, but I can buy or download it anywhere so far (because it is not out yet). Is there anywhere I can download it?