Worth mentioning for anyone who happens not to know about it that there's a massive repository of out-of-copyright (either by time or decision of the composer) music scores and recordings for all instruments by a huge number of composers. Using the 'genre' section is useful for finding music of an appropriate level for performers.

https://imslp.org/wiki/Category:Composers https://imslp.org/wiki/Main_Page https://imslp.org/wiki/IMSLP:View_Genres

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