Because of the cross-disciplinary nature of ethnomusicology, you should be creative with your searches and try alternate terms and subject headings. Some terms you may want to try:
folk music
national music
sound and anthropology
ethnomusicology
world music
soundscapes
aural culture
music and (country or region of study)
music acoustics
music and sociology
traditional music
ethnic music
On the Library Shelves:
Ethnomusicology,
browse: ML3797.6-ML3799
Music of regions and countries,
browse ML3545--,
Physiological aspects of music,
browse: ML3916--ML3918
