The pilot reported that he had just bought the airplane and was not familiar with it. While making his first landing he made a steep approach, hit "hard", and bounced. After the second impact the airplane exited the runway and impacted terrain. The impact resulted in a complete separation of the nose gear and substantial damage to the fuselage, the right wing and the elevator. The pilot reported no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation. He also reported that the accident was his fault and would not have happened if he had only first gotten a new aircraft check-out from a flight instructor.