Good to note: Lists of repertoire are often featured in music-related journals & magazines. Search Music Index and IIMP using the subject "bibliography" to locate repertoire for a specific instrument or ensemble. Example: guitar AND bibliography
Tyler, James and Paul Sparks. The Guitar and Its Music : From the Renaissance to the Classical Era. Music Library Stacks ML1015.G9 T96 2002
Baron, John H. Chamber Music: A Research and Information Guide. Mus Lib Ref ML128.C4 B37 2010
Lindeman, Stephan D. Concerto: A Research and Information Guide. Mus Lib Ref ML128.C84 L56 2006
Lyons, David B. Lute, Vihuela, Guitar to 1800, A Bibliography. Music Library Ref ML128.S7 L9
MacAuslan, Janna. Guitar Music by Women Composers : An Annotated Catalog. Music Library Stacks ML128.G8 M33 1997
Smith, Dorman H., and Eagleson, Laurie. Guitar and Lute Music in Periodicals : An Index. Music Library Ref. ML128.G8 S64 1990
Maroney, James F. Music for Voice and Classical Guitar, 1945-1996 : An Annotated Catalog. Music Library Stacks ML128.S3 M37 1997
Rezits, Joseph. The Guitarist's Resource Guide : Guitar Music in Print and Books on the Art of Guitar. Music Library Ref ML128.G8 R5 1983