Medieval Music - Wikipedia article providing an overview of the period with summaries of musical developments plus internal references to related people and topics and external links. - http://en.wikipedia.org/wiki/Medieval_music
Medieval Period (1200 - 1450) - Introduces those responsible for developing harmony and added instrumentation to Western music. From The Conservatory at Humanities Web. - http://humanitiesweb.org/human.php?s=c&p=i&a=l&ID=1
Medieval, Renaissance, and Traditional Music - Collection of MIDI audio files freely downloadable from Kunst der Fuge. Sorted by nationality and author. - http://www.kunstderfuge.com/renaissance.htm
Music History 102: The Middle Ages - Composers, major styles and developments, illustrations, and Real Audio RAM sound files from the Internet Public Library. - http://www.ipl.org/div/mushist/middle/index.htm
Middle Ages: 450-1450 - Introduction to the Medieval Era from Essentials of Music linked to details on historical themes, musical context, style, and composer biographies. - http://www.essentialsofmusic.com/eras/medieval.html
The Medieval Sound - David Munrow - CD - Introduction and demonstrations of individual medieval instruments, followed by suites of renaissance and Elizabethan dances. - http://www.baroquecds.com/02Web.html
The Central Middle Ages (1100-1350) - Period overview and biographies of individual composers of early music complementing Here Of A Sunday Morning the radio program. - http://www.hoasm.org/PeriodII.html