So many who love to sing are drawn to the immediacy and essential simplicity of the music we commonly call folk. Folk music, in fact, can serve as the perfect entry point for those just starting on their singing careers because of the ways in which it sidesteps the strictures of classical forms without giving up the fundamentals of professional singing techniques. In So You Want to Sing Folk Music, singer and writer Valerie Mindel demystifies this sprawling genre, looking at a variety of mainly traditional American musical styles as well as those of the folk revival that continues in various...