A publication of the Archaeological Institute of America
Do a Google search for "Alexander the Great" and you'll find 1.12 million websites that at least mention him. Undoubtedly thousands of these sites focus on him, and wading through them is impossible for the average person, no matter how interested in the subject they are. Here we've kept the list to a bare minimum, striving for usability rather than overwhelming detail.
The "Alexander the Great on the Web" site by Tim Spalding is billed as a "comprehensive guide to 1,000 websites about Alexander, sorted, described and ranked." The links are categorized as Web Biographies, Alexander's Character, Armies and Battles, Oliver Stone's movie Alexander, Documentaries, Alexander in Literature, and Primary Sources on the Web. This is probably the best Alexander site.
Another good overview site is called "Alexander the Great's Home on the Web." Created by Thomas William-Powlett, it has articles on subjects such as Alexander's sexuality, his horse, and so forth, along with a trivia quiz.
If you just want the basics, there's the "Alexander the Great" page of Boise State history professor E.L. Skip Knox. It provides the biographical outline and explores topics such as the Macedonian army, the organization of Alexander's empire, and more. Longer biographies of Alexander and Philip are on the Livius site.
Maryland Public Television still has online the website companion to Michael Wood's four-hour series "In The Footsteps Of Alexander The Great." In addition to general information about Alexander and the usual links page, this site features a downloadable teacher's guide that will help educators "incorporate series topics and ideas into your social studies, science, mathematics, and language arts high school curricula. Many activities can also be adapted for younger students."