I was perplexed by this at first also. If you have ADSL, then you automatically have at least one e-mail address. You have a card from Hinet with your password details, right?
Look on the back at your username. Your email address is that username @ msa.hinet.net. So if it's 800100, you are
800100@msa.hinet.net. You can also go to the Hinet ADSL website and change your e-mail address to something more sensible.
http://www.hinet.net/support/chtdcsc.htm?index.htm
You can view your mail here also if you don't have e-mail software.
http://webmail0.hinet.net/cgi-bin/mail.cgi