The Gallaudet Encyclopedia is online and you can look up Japan and Japanese for background information. Check out the Sage Encyclopedia of Deaf Studies as well. The NTID Deaf Index citation (not full-text) database will help you find conference papers, articles and books. Use the abstract field in the left hand column and type in your keywords.
The Gallaudet Index to Periodicals is also a citation database. You can search by keywords, person's name (last name, first name), title or subject.
If you are looking for Japanese Deaf people, use the Gallaudet Guide to Deaf Biographies. You can search by person's name and region.
You will need the title of the book to locate the book by using the RIT Libraries Catalog. You will need the periodical or journal title to locate the journal article by using the Journal Finder.
If you have a citation, try the Citation LInker to locate the material.
Tip: Use the bibliography or references at the end of the papers to find more works.