Emily,
Sorry for the belated response. It has been years since I have been on this site. Not sure if we are related. I can tell you since I initiated my family search I have found a lot of good info but it was not through this site. I first started with sending a letter to the Japanese Consulate General in Honolulu with a small fee. Must provide them your great-great grandparents names. The consulate will send you a document that is in Japanese with the address they came from in Japan plus when they arrived, their birth dates, their children names and birth dates, etc. You might have to get it translated if they did not provide a translated copy. The next step I did was send a letter to the Kumamoto City Hall in Japan which is the prefecture they came from. I added copies of birth certificates from me, my father, my grandfather and great grandfather to prove the family line. Their is a fee as well. You will request in the letter for your family's koseki tohon (family registery). Once you get that, again you will need to get it translated to english. Well worth the cost and effort. I was able to get at least two koseki tohon for my great great grandparents and the one before them. My goal of reconnecting with living relatives from Kumamoto has not come true yet, but still trying. Well, hope this helps you on your journey and mahalo for the message. George Tsukamoto from Kauai.