Hosho are gourd shakers commonly played as accompaniment in Zimbabwean style marimba ensembles.
One good source for hosho is Mylinda King who is also a dedicated performer/educator. She can be reached through her website:
Another source for hosho is the non-profit organization MBIRA run by Erica Azim who is also a dedicated performer/educator. MBIRA supports Zimbabwean musicians and instrument makers, and their families, through worldwide Zimbabwean music education, recordings, and performances.