DC Circuits
A series of tutorials from the University of Guelph.

The Electromagnetic Spectrum
An excellent resource for students from NASA.

Gallery of electromagnetic personalities
Biographies of important physicists and their contribution to the study of electromagnetism

How electric motors work
Another easy to understand description from Marshall Brain's How Stuff Works site.

Tesla : Master of Lightning
A PBS site for students, teachers and researchers.

Theatre of Electricity
From the Boston Museum of Science