Wikipedia: Musical Genre  
   Brief explanation of the way styles can be defined by region, chronology, technical requirements, marketing trends, or the ideas of critics. Extensively linked to sub-genres and examples of significant artists.
   http://en.wikipedia.org/wiki/Musical_genre

American Music Center: Musical Genres  
   Links to articles and representative artists of styles such as pop, rock, blues, folk, classical, theater, jazz, and world music.
   http://www.amc.net/links/genres.html

Duke University Library: Women in Music By Musical Genre  
   Text lists and links to library resources such as books, periodicals and recordings on women performers and composers by musical genre.
   http://scriptorium.lib.duke.edu/women/mugenre.html

InfoUSA: Musical Genres  
   Links organized by genre such as blues and jazz, classical and opera, folk and country, and early American music.
   http://usinfo.state.gov/usa/infousa/arts/genres.htm

Audiogalaxy: Glossary of Musical Styles  
   Hundreds of sub-genres defined in non-technical language mentioning sample artists. Organized under headings such as pop, hip-hop, jazz, blues, classical, Latin, modern rock, rock, and heavy metal.
   http://www.audiogalaxy.com/list/glossary.php

Ectophiles Guide by Genre  
   Self-described "Guide to Good Music" from a group founded in 1991 to support the music of singer Happy Rhodes. Links to artists, almost entirely female vocalists, sorted by genre such as pop, blues, experimental, performance art, beautiful and f
   http://ectoguide.org/genre

Music Classification by Genre: System Performance  
   Research project completed in 2003 by Mitali Banerjee at Rice University used automatic process to determine musical genre of audio samples.
   http://cnx.rice.edu/content/m11690/latest/

DataDragon: Music Genre Sampler  
   Children's site with simple definitions of a few genres including rock, Celtic, and classical with artist and site links.
   http://datadragon.com/education/genres/

Christian Music Place: Artists by Genre  
   About two dozen musical genres including blues, a capella, dance/techno, and Southern gospel, with as many as several hundred links to Christian music artists in each.
   http://www.christianmusic.org/cmp/artists/index.cgi?command=Display_Genre

Music Web Hunter: Styles & Genres  
   Ken Davies has grouped resources in five categories: classical, folk/ethnic/world, jazz, musicals/operas/theater, and pop/rock/country.
   http://www.kendavies.net/musicwebhunter/stylegenre.html

Indiana University School of Music: Genres  
   Categorized links organized by researchers at the William and Gayle Cook Music Library. Unusual categories include 20th-Century music, ancient music, band music, tango, flamenco, ragtime, and choral music.
   http://www.music.indiana.edu/music_resources/genres.html

A Taxonomy of Musical Genres  
   Two French experts re-define genres to improve musical databases for electronic distribution, paper submitted to a conference in Paris in 2000. [PDF]
   http://www.csl.sony.fr/downloads/papers/2000/pachet-riao2000.pdf

AllMusic Guide: Genres  
   Musical style sort with detailed definitions from site maintained by musical journalists. Requires free registration.
   http://www.allmusic.com/cg/amg.dll?p=amg&sql=73:

Representing Musical Genre: A State of the Art  
   Journal of New Music Research article from 2003 discusses manual, prescriptive, and emergent approaches to genre classification for the European CUIDADO project, Content-Based Unified Interfaces and Descriptors for Audio/Music Databases Available Online. [PDF]
   http://www.idiap.ch/~paiement/references/to_read/music/genre_classification/pachet-02c.pdf