Library databases have access to articles from journals, magazines, and newspapers. Every database has different content. This makes it important to use a database that has content on the subject you are researching. In addition, be sure to search in more than one database to find information.
Check out these recommended databases to get started:
NOTE: These guides from Oxford Music Online focus more on classical music, rather than popular music.
Check out these tips when deciding to use an online source. Always be skeptical.