PBS
Themistocles, Greek General
Wonderful biography of Themistocles, the great Athenian general and politician who established the Greek navy.
Boise State University
European History: The Peloponnesian War
PowerPoint style site traces the beginnings of the Peloponnesian War, the Delian League, and the Archidamian War. Includes references and further reading.
PBS
The Battle of Plataea
Background and description of the Battle of Plataea. Does a good job of discussing the different versions of the battle presented by historians.