Begin your research with tertiary sources. They will help you:
Examples include:
Encyclopedias: Authoritative reference to get an authoritative overview of a topic or look up terms.
To Find: search "music encyclopdias" in the online catalogue or browse the ML 100 section of the library.
Premier reference for musicians and musicologists. Covers the New Grove Dictionary of Music, the Oxford Dictionary of Music, and the Oxford Companion to Music.
The New Grove dictionary of music and musicians ML 100 N48 2001 20 vols. Earlier print edition of the respected encyclopedia.
Thematic Catalogues: organize a composer's entire corpus of work. to qualify as a thematic catalogue rather than a bibliography the work must include inicipits (first few bars of the music) . They typically also yield information as the original date and place of composition, manuscripts, early editions, and other details to aid scholarly research. Thematic catalogues exist for specific composers and repertoires.
To Find: search "<composer's name> thematic catalogue" or browse the ML134 section of the library. For thematic catalogues for particular repertories search "<the repertoire> thematic catalogue" as in "vocal music thematic catalogue".