There are various excellent resources on the web illustrating Shotokan Karate kata, as performed by members of the JKA. Several very useful videos are available on youtube, including  heian shodan. You can select various kata in the video player below using the button in the top left corner.

Other kata videos include: heian nidan, heian sandan, heian yondan, heian godan, tekki shodan, tekki nidan, tekki sandan, bassai dai, kanku dai, empi,and  jion