Magnetospheres other than Ours
Most large planets in the solar system have magnetic fields, probably produced quite differently from ours. The giant planets also have trapped radiation belts--indeed, those of Jupiter and Saturn are far more intense than Earth's, and their polar auroras have been observed by telescopes from Earth and aboard spacecraft. (The pages are parts of larger collections)
http://www.phy6.org/Education/wotherms.html
http://www.phy6.org/earthmag/mill_8.htm

Radio Jove
"Radio Jove" is an educational outreach project in the area of planetary radio astronomy. The project is intended to give high school students and college undergraduates hands-on experience in planetary radio astronomy by observing radio emissions from Jupiter and the Sun with a simple radio telescope built from a kit that can be ordered through the Radio Jove web site. The site provides guidelines on basic observing methodology, prediction tables for jovian radio storms, etc. Data analysis software can be downloaded from the site. Although parts of the site are still under development, the Radio Jove project is well under way. Radio Jove is a collaborative undertaking by NASA Goddard Space Flight Center's Space Science Data Operations Office, the University of Florida's Astronomy Department, and the Florida Space Grant Consortium.
http://radiojove.gsfc.nasa.gov

Galileo Mission Web site
Although not specifically concerned with the jovian magnetosphere and upper atmosphere, this site is a rich source of information about the exciting new discoveries that have been made during Galileo's five-year tour of the Jupiter system. The Galileo site provides clearly written background information on Jupiter and its moons, regular press updates and mission status reports, and descriptions of the spacecraft and of the operational aspects of the mission. There is an extensive gallery of images.
http://www2.jpl.nasa.gov/galileo/