ASDA are selling Call of Duty - Black Ops for £36.97 but you can get the Strategy Guide and a Call of Duty Black Ops T-shirt for £46.97, normally worth £53.91 if purchased seperately:

Call of Duty Black Ops - Xbox 360 | Xbox 360 | ASDA direct

Add Call of Duty Black Ops on Xbox 360, plus the Call of Duty Strategy Guide and the T-shirt of your choice in Medium, Large or XL all for a fantastic price of £46.97!
Limited to one item per order