Today I need help finding my grandfather family in Japan

This is a long shot i know but there we go, 30 years ago my oldest uncle came to Japan and founded some of his dads' relatives, they present him in a book of the family tree. the book got lost and also the contact with the family (name is Hoshihara) from Kagoshima, I wonder if anyone knows how to contact the family there and or have use this service to have this family book printed? anything will help.