The 13-hour student pilot lost directional control of the airplane during his initial solo flight while on his third touch-and-go landing on Runway 17R. The student pilot reported that right after touchdown, the airplane exited the left side of the runway, passed through a grass median, crossed parallel taxiway "foxtrot" and impacted a taxiway sign, coming to rest in the inverted position. In a telephone conversation with the NTSB investigator in charge (IIC), the student pilot added that the airplane "abnormally veered to the left" after touching down. The student pilot further stated that he retracted the flaps and added power for the go-around after the airplane started to veer left. He did not recall if he had applied brakes during the landing roll. Runway 17R is 7,008-feet long and 100-feet wide. The winds at the time of the accidents were from 050 degrees at 7 knots. Multiple attempts to obtain a completed Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2) from the pilot were unsuccessful.