Interactive NASA Observatorium on satellite orbits and Kepler's Laws tutorial.

http://observe.arc.nasa.gov/nasa
//education/reference/orbits/orbits.html

Pictures from Newton's Principia and three user-controllable JAVAscript simulations (one for each of Kepler's Laws) nicely illustrate satellite motion.

Online biography from the MacTutor History of Mathematics archive at the School of Mathematical and Computational Sciences, University of St Andrews, Scotland.

http://www-groups.dcs.st-and.ac.uk/~history
/Mathematicians/Kepler.html

Kepler was the last scientific astrologer and first modern astronomer. He worked on geometry, calculus and orbital mechanics. There is an extensive set of materials describing the calculation of orbits available. Additional information on Kepler is found in the Rice Catalog of the Scientific Community in the 16th and 17th Centuries.

NASA's Liftoff site containing the Space Academy rocket scientist tutorial.

http://liftoff.msfc.nasa.gov/academy
/rocket_sci/rocket_sci.html

This site tells you all about the business of launching shuttles, near earth and geosynchronous satellites.

Check out the the satellite page with the J-Track satellite tracking applet to see what's orbiting now, where it is and when you can next see it in the night sky from your location. There's a handy GMT clock and weather map too.