Some tips on house training:

Take him out every few minutes (15-30), right after playtime, right after eating, right after napping. Yes, it's just like having a baby around. If he starts to go in the house, try and catch him in the act and pick him up and put him right out. Don't wait until he's already done. When he does it outside, praise, praise praise (cookies help, too!) Good Luck, and let us know how he does.