I know that fax is getting outdated, but I still need to send one.
You can send faxes from convenience stores.If you are not good at Japanese, Seven Eleven shops have photocopy machines with English menus.
The machines are coin-operated, and you can easily locate them in one corner of the shop.The cost is usually 10 yen per page (local). Do carry 10,100 or 500 yen coins to use with the machine.