You will find Shells on the ground all the way up to NYC and north even.... NOt from battles but from live fire drillsAs far as I know there's no fests by any Rev War battlefields. Probably some along sites where there were skirmishes in the south but not where a lot of shots were fired. Civil War era ammo was more bullet shaped though the technical term ball is still used for standard ammunition.
I'd love to tour some of the Civil War battlefields in the South one day.