Mark Harmon never was an Olympic gold medalist. You may be confusing him with Mark Spitz who WAS an Olympic gold medalist swimmer in the 1972 Olympics.
Yu-Na Kim was the women's gold medalist
Leisel Jones is an Olympic gold medalist swimmer from Australia.
Eleonor Simmons
Maris Strombergs
The women's downhill gold medalist at the 1964 Winter Games in Innsbruck was Christi Haas of Austria.
Murray Rose
an olympic swimmer and gold medalist
The first US gold medalist in the Modern Olympics was James Connolly in the triple jump in the 1896 Games in Athens.
Paavo Nurmi (FIN)
2006 Olympics medalist for ice hockey are: Gold medal: Sweden Silver medal: Finland Bronze medal: Czech Republic
Tara Lipinski was the youngest figure skating gold medalist. She won it when she was 15 years old in the 1998 Olympics.