on this link you can go right there and buy! Take a look through the whole list, there are dozens of titles, including box sets of The Comic Strip Presents and 30 Rock, for example, at good prices, and some single DVDs are under £3!
But hurry, offer closes on Sunday!
*UPDATE: Well, the offer has now closed, but they're still offering it for under £40. Tesco's bigger stores have it at £31, and HMV 's price is £39.