Hi James, welcome to the forum. Could I invite you to introduce yourself here
, and then you'll be given a bit more information about the forum and how to use it.
As for your question, I can't recall any contemporary Japanese music on the forum at the moment. You might try asking again in "Public Space". It would be useful to specify whether you are looking for scores or recordings, and also whether you are looking for music uploaded to the forum, or for ideas of where to look more generally.
Classical Guitar Forum.
"Experience is something you don't get until just after you need it." - Steven Wright