The airplane collided with two fences during an attempted go-around. The pilot was performing touch-and-go practice takeoffs and landings in an effort to improve his landing technique. After completing one landing he continued around the traffic pattern for a second attempt. While on short final approach he had the airplane configured at an airspeed of 70 knots and retarded the throttle control to the idle position. As the airplane descended, he added nose-up trim and subsequently heard the stall warning horn. The airplane's tail struck the runway surface and the pilot opted to perform an aborted landing by adding full power. The airplane was configured with full wing flaps, the landing gear in the down and locked position, and the speed brakes extended. The airplane began to porpoise down the runway and the pilot pulled back on the control wheel in an effort to become airborne. The airplane continued off the end of the runway and collided with a fence. It then crossed a road and came to rest after impacting another fence. The pilot reported no preimpact mechanical malfunctions or failures with the airplane that would have precluded normal operation.