By “last year” I assume that you are speaking of 2001. How many days were you in the ROC during 2001?
You should have a Taiwanese friend stop by the tax office and pick up an “agency” type of form, so that he/she can be appointed as your agent to handle your taxes. Then you will need to give him/her all your withholding receipts, copy of passport (including all pages with entry and exit stamps for late 2000 and all of 2001 and your exit in 2002), and a copy of your ARC (if any), and then it should be possible for that person to file your tax return and have the rebate sent to their address.
However, the check will undoubtedly be in your name. Do you have a local bank account into which it can be deposited? Then your friend could withdraw the funds and do an electronic transfer of funds to you, or perhaps you could withdraw directly from that account with your current ATM card???