The Yamagata Conference Committee Members (CCM) help, plan, co-ordinate, and facilitate the three main prefectural seminars for ALTs: the New JET Orientation, Skills Development Conference and Regional Seminars.
They provide helpful resources on their Yamagata JET Community Share Drive, ranging from lesson plans to general information about Yamagata, things related to the JET community, and more.
It is a shared drive, so anyone can contribute to it. If you want to add something, have a look at the instructions in the shared drive for more details.
Here is a document on the JET support system structure, provided by CCM.