Yeah, I would definetly notify the police and let them know that the vin is missing tho. They may be interested or know something you dont (maybe the previous owner etched the vin number in another place or his initials). Plus if you did rebuild it and the cops caught up with you, you may lose the entire investment because it was "suspicious" without the vin.
My shee and my brothers were stolen a few years ago just 3 days before Christmas out of our shed. They eventually caught the individuals trying to steal something else from close by and they admitted to taking ours. They said they parked them in the woods and mine had been stolen from them and the other had the motor and stuff taken from it but the frame was still there (cops never went to find the frame from what I know) Punks were juveniles and ordered to pay restitution but I have only seen about 100 bucks and my brother has seen even less. I think my old bike is still in the tri-state area (it was an '01 blue, all stock except for a complete set of holeshot tires front & rear, no tank stickers except a skull and cross bones on the left side of the tank, and a PRM rear skidplate with DG rear oval bumper that mounts off the rear swingarm). I tried to talk to the NJ courts to find out what the deal was with not getting my money but they were from NY and there was a problem between the two states communicating regarding these punks. They do have a black mark on their credit so if they ever go to do anything they have this on their record and have to pay it off if they ever plan on a new car, house, or any large purchase.
But even my quad back or payment still will never equal the pain and hurt I felt when I woke up and found one of my most prized possesions stolen.
Nick