A little "ooops", only of interest to those who have already got a harp-l web account.
I forgot to edit the account creation script to point you at your new "home page" when you finished registering. The "details" screen it pointed you at instead is now defunct.
A lot of people managed to work out for themselves that they have to press the "Home" menu item to get to their home page and edit their "profile", but some haven't.
So. If you were wondering where you were supposed to go from there ... try:
http://www.garply.com/harp-l/home/
... which will prompt you for your name and passwd. Your "home" page will explain what you then need to do in order to set up your profile/bio.