KUKKIWON WORLD TAEKWONDO HEADQUARTERS
http://www.kukkiwon.or.kr/english/index.jsp
The Kukkiwon is the Central Gymnasium for Taekwondo in Korea. Its goal is to set standards, provide information and training, certify and regulate DAN testing, and to promote TKD world wide. It has great information about Taekwondo and has excellent videos of forms (poomsae).

RELATED LINKS

WORLD TAEKWONDO FEDERATION
http://www.wtf.org/
The World Taekwondo Federation is the International Federation governing the sport of Taekwondo with Olympic affiliation. This site offers a wealth of information about forms (poomsae), sparring rules, coaching, and competitors.