If your are looking for peer-reviewed and/or scholarly articles for research, I recommend you start with one of these databases. These are not the only places where you can find music-focused research, but it is a good first step.
If you are looking for an in-depth, full-length treatment of a particular topic, books are a good place to begin. Searching the library catalog (aka LINUS) is how you find both print and e-books owned by the library. If you can't find what you need in our collection, use LINK+ to search collections of other academic libraries.