Here are some popular swimming links

YMCA Nationals  http://www.ymcaswimminganddiving.org/

Maine Swimming  http://www.maineswimming.org/

USA Swimming http://www.usaswimming.org/

Swimming World Magizine http://www.swimmingworldmagazine.com/

Harvard Swim Index http://www.hcs.harvard.edu/~swim/links/

Web site Swim Photos http://www.greggtehennepe.com.