John Philip Sousa

Sousa wrote 136 marches and effectively defined what a concert band is. Everything he wrote is out of copyright in the United States, which is why the catalogue is thick with free editions.

The Stars and Stripes Forever, The Washington Post and Semper Fidelis are the ones everyone plays. Band sets are published complete with parts; individual instrument parts and piano reductions are separate purchases, and buying a "score" when you needed a full set of parts is the standard error here.

Modern editions sell on the editing rather than the music: the original parts have inconsistencies and errors that a century of performance has corrected, and a good recent edition incorporates them. For a school band, a graded simplified arrangement is usually the right choice over the original, which is harder than its familiarity suggests.