There are several ways to send home money from Japan. Popular options have been Lloyds Bank and the post office. The post office used to be cheaper than Lloyds but the handling fee has since increased to 2500 yen. Although this is more expensive than Lloyds, non-Lloyds TSB customers will also have to pay a further handling fee of around 1500 yen (or the equivalent in your home country) at the other end when using the Lloyds Bank remittance service. This said, payments to Lloyds can be made at ATMs making it slightly faster and the correspondence you receive will be in English.
If you are sending larger amounts of money, you may want to consider using a Japanese bank. They may have higher handling fees, but the rates may be better than Lloyds.
GoRemit (Formerly GoLloyds)
This service allows you to transfer money from an ATM of your Japanese bank directly to a specified account in your own country. Provided that you make the payment before 3pm on a weekday, it is usually handled on the same day. The flat rate is 2000 yen per transaction (additional charges made by your bank back home will differ).
URL: http://www.goremit.jp/individuals/applyonline/en 
Visit the above link to start your application. Send the application form and the necessary documents to:
Shinsei Bank GoRemit
Nihonbashi Muromachi Nomura Building,
4-3, Nihombashi-muromachi 2-chome,
Chuo-ku, Tokyo, Japan
Mitsui Sumitomo charges higher handling fees than GoRemit (Shinsei Bank), and their service is purely in Japanese, but the rates appear to be a little better. If sending larger amounts of money (over $10,000, for example), it may be the less expensive choice.
- GoRemit: https://www.goremit.jp/index/en
- Mitsui Sumitomo: http://www.smbc.co.jp/ex/ExchangeServlet