Just spotted this, can't see it listed elsewhere, seems to be the cheapest about - XBox only at this price
Experience the magic, excitement and wonder of Hogwarts School of Witchcraft and Wizardry in Warner Bros' LEGO Harry Potter: Years 1-4, for the Microsoft Xbox 360.
LEGO Harry Potter: Years 1-4 is based closely on the first four books and films of the franchise to bring you an authentic and fun-filled adventure game. Choose from over 100 playable characters including the eponymous Harry, along with the likes of Hermione Granger and Ron Weasley, and immerse yourself in a stunning 3D Lego representation of iconic, immediately recognisable settings!
Build adventures, mix potions, and fly on broomsticks in the spellbinding and dazzling adventure - LEGO Harry Potter: Years 1-4!
Game Release date 6/29/2010
Obviously Also available at Dixons, being the same chainhttp://www.dixons.co.uk/gbuk/microsoft-lego-harry-potter-years-1-4-06773989-pdt.html
Don't forget Quidco for that extra bit off