Linsay, Jennifer.Javanese Gamelan: Traditional Orchestra of Indonesia, second ed. Singapore: Oxford University Press (1992). A short introduction to the subject. Includes many good color photos of gamelan instruments in performance.
Becker, Judith.Traditional Music in Modern Java: Gamelan in a Changing
Society. Honolulu: University of Hawaii Press (1980). Provides detailed
information on gamelan music as well as modern developments in Javalese gamelan
and the social context.
Kunst, Jaap. Music in Java: Its History, Its Theory, and Its Technique,
2 vols., 3rd rev.ed., E.L. Heins, ed., The Hague: Martinus Nijhoff (1973).
A comprehensive study of Javanese music. The early chapters contain a number
of writings about the history of gamelan instruments, tuning, and performance
in Java. Vol. 2 contains photographs and a bibliography.
Websites on Gamelan
Bali & Beyond
A site maintained by a group of Los Angeles performing artists. Provides more
detailed information on gamelan music, instrument making, dance and shadow