This site provides a listing of hundreds of dances with links to all the available online resources for them, including many of the other pages listed here.
This is a set of dances that are a good place to start for beginners. It includes some basic information about each style of dance and dancing in general, as well as where to find recorded music.
This is a great place to start looking for information on Renaissance dance. The list of links there is far longer than what will be found on this page.
This is a set of instructions for many common SCA dances, written by Master Gregory Blount of Isenfir (Greg Lindahl). Most are linked to from the database.