Where are you looking? Youtube? Downloading? Actual crate digging?
Where and how will have an impact on what you find, but in general (if I understand you correctly), you are looking for traditional Japanese folk music with instruments like the shamisen, shakuhachi, the koto, and the sheng (I forget the Japanese name right now).
If you are digging, look in your record stores' "World Music" section. If you are Googling, try those instrument names, as well as "taiko drums." You can also find taiko, koto, and shamisen apps in the Apple store that might be convincing enough to help you make your own samples...
GJ