Here’s an interesting resource for all you musicians out there. The International Music Score Library Project (IMSLP) contains 60,000 works that are in the public domain in Canada. One can do a keyword search for works by composer or title. You can browse using these categories too, in addition to browsing by time period, nationality, melody, instrument and genre. IMSLP also includes recordings; these are either in the public domain or are included under a creative commons license.
This letter A is not only the IMSLP’s logo, it is also from one of the first printed books of music, dating from 1501.