The pilot was conducting a series of practice accuracy landings in preparation for a checkride. He reported that he inadvertently forgot to extend the landing gear. He added that he did not remember hearing the landing gear warning horn just before touchdown because he had allowed himself to become fixated on maneuvering the aircraft to the precise landing point. The airplane touched down on the runway surface with the landing gear retracted, causing substantial damage to the fuselage. The pilot reported there were no pre-impact malfunctions.