in quest of the best web sites for collectors
Music on Stamps
Bagpipes on Postage Stamps
An excellent display of stamps depicting bagpipes.
Beethoven on Stamps
An extensive collection of stamps devoted to Beethoven.
Bach on Bach
A site devoted to the life and works of Johann Sebastian Bach on stamps.
Motivgruppe Musik
Motivguppe Musik is a German organization for collectors of music on stamps. The site is in English as well as German.