International Space Station Locator Sites

NASA realtime tracking data
An active visual world map of the ISS location in orbit

NASA SkyWatch
Java application providing worldwide picture of when and where the ISS, space shuttle and other spacecraft can be seen with the unaided eye as they pass overhead

A more detailed interactive NASA map with variables, such as weather

Heavens Above
Spaceflight and astronomical information with times of visibility and tracking star charts

... also may be of interest: National Air & Space Museum: Collections
and National Aviation Hall of Fame