Type search words into the search box, making sure to select the "Books and Media" button.  Then click the green "Search" button with the magnifying glass at the bottom.

Notice "Refine My Results" on the left side of the results screen.  Click on "Scores" under "Refine My Results."

You now have a list of scores in the Music and Dance Library.  Click on individual titles for more information or look for them by call number in the Music and Dance Library stacks.