Steve was apparently somewhat paranoid, as he had security cameras in his home, as well as an alarm system and exterior cameras. He also kept his hunting equipment in a locked closet.
When Sam and Dean try to figure what happened during Sam's black out, Sam is able to lead them to a large, heavily secured home. When they see the house has been broken into, they enter and see the floor is covered in broken glass and scattered items. In a back room, they come across Steve's corpse on the floor with a deeply cut throat. They soon learn that the man was a hunter, and notice a security camera in the room.
On the tape, Sam is shown fighting with Steve. The fight moves off-camera and then Sam drags Steve's corpse back into the frame, he kneels with Steve pulled up against his legs and slits his throat.
After leaving the home, Sam learns his name through a letter he found from his daughter, as well as that Steve had hunter friends who would avenge his death if they knew who killed him.