It depends on the Museum you go to.
The AirForce Museum in Dayton Ohio, has lots of forgin stuff in it, Me 262, D9, Me 163, MC 200, Great gun coloection, JU 88, JU 52, and much micu more.
The Pauel E Garber Facality, has an amasing colection of Planes: Shinden, Il-2,Mossie, Francis,Grace, Jill,Me 410. He 177Engine (only:( ), and Much Much more.
It real depends on whear ya go, some of the local air museum are heavy in US stuff because the rare enemy planes are in the National museum's which are spread aroiund the country.