One of the best ways to find scores in the library is to browse. At Wright State, we use Library of Congress classification. This means that music materials have call numbers that begin with M. You'll find the M section in the Bound Periodicals area on the second floor of Dunbar library.
Music materials are organized as follows:
If you're looking for a score, look in the materials that have an M followed immediately by numbers:
For a more thorough overview of how scores and books about music are organized, see the Library of Congress Classification Outline for Music or Sourcebook for Research in Music (Reference ML113 .S46 2015), pp17-23.
As you search for music resources, you may need to use terms like Opera Omnia, Sämtliche Werke, Gesamtausgabe, or Oeuvres Complètes. For a good list of foreign language terms used in music, see Sourcebook for Research in Music [Reference ML113 .C68 2005] pp 8-14.
You'll probably come across some terms, titles, or names that use international characters (e.g., Die schöne Müllerin). When searching the library catalog, leave out international characters. "Die schone Mullerin" will get you the same results as "Die schöne Müllerin." If an alternate spelling is acceptable in place of an international character, use whichever spelling is standard. For example, Arnold Schönberg's last name most often appears as "Schoenberg"; use that to search. If you are unsure which spelling is standard, combine your search terms using "or" (e.g., schonberg or schoenberg).