As has been stated, your puppy needs to be taken out on a very regular basis. Dogs don't just automatically know what to do.

The best book I have seen is "How to Housebreak Your Dog in Seven Days" by Shirlee Kalstone http://www.amazon.com/gp/offer-listing/0553346156/ref=sr_1_olp_1?ie=UTF8&s=books&qid=1225997 800&sr=8-1. It's the we recommend to our puppy buyers who want help with the housebreaking; and it's dirt cheap for the used ones. It uses crate training as the method of housebreaking; I also happen to believe very strongly in crate training. Just don't believe the 7 day part of the title, ain't gonna happen that quick!!

Good luck with your pup and be patient with him!