Ohh I just read this in The Culture Shock. If you want to teach him to play hide and seek, you have to start easy.. leave it out in the open and say "Where's your toy!!" and give him hints if you have to, but when he picks it up, reward him. Then keep doing it until it seems like he knows that he's supposed to be searching for something and hide it better, and even hide treats with the toys or inside the toys (like kongs and stuff). Eventually you should be able to hide smelly treat-filled toys and just hide them all over, and when you give the command "Where's your toy!!", they'll know good things are lurking around and they'll hunt for them. If treats are hidden inside toys, it should be even better because they're automatically rewarded for finding the toy. The book even talked about hiding a bunch of things for them before you leave for work (if you give your dogs free roam of the house) and this game can keep them busy for hours.
Hope that helps.. you should really read The Culture Shock by the way, it's an awesome book!! I'm learning how to teach my dog to play games with me.