Gail
First of all your friend knows who the person is, or at least believes that he does. As far as I am concerned this is far more than an eBay matter which may only result in the person getting booted off eBay (BIG DEAL, THEY WILL STEAL ANOTHER IDENTITY AND START P AGAIN).
This is a criminal matter and should be reported to the local police authorities IMMEDIATELY.
Have your friend call the local police. They will refer him to a 1-800 number where the agency operates a joint task force between federal, provincial and local police authorities as well as the 2-Canadian credit bureaus.
What has happened to your frined is known as "identity theft" and is far more serious a matter than a prank. I know as I have been the victim of identity theft when I lived in the US.
Again, this should be done immediately or it could take your frined years to recover from the damage that other person could do to your friend.
Malcolm