Simple game website

I need a simple spot the ball game website The simple version goes like this. • Customer comes to website and picks a game • When he enters the game, he sees a photo • When he clicks on the photo, he puts that specific x-y coordinate in his shopping basket • each coordinate costs €1 • when he checks out, he has to pay for his basket (for example 5 coordinates) • his purchase is stored in the dbase and at the end of the run, the first customer with the winning coordinate gets the prize. • second option is that he sees if he has got the winning coordinate and if so he is taken to the collect your prize page. What I need is somebody to build the back-end. We deliver the design ourselves, but we need a back-end where we can store customer details, prizes etc etc. basicly its an adapted e-comnmerce system, only selling coordinates.