Key for sites with a ~tilde eg http://users.isp.com/~someone

I have a site which is lookeded as noted above. However, when I look at
the site with an ftp client, it shows all the files in a www
subdirectory.

For the life of me I can't find a way to get a map key. I've tried:

http://users.isp.com
http://users.isp.com/www
http://users.isp.com/~someone
http://users.isp.com/~someone/www
http://users.isp.com/www/~someone

The first two yield keys which do not work and any with the tilde ~ get
an error message from google indicated a malformed url

I would greatly appreciate any help so I can get a google map on my
site. I've been using http://www.mapbuilder.net/ to build the code, and
inserting the key generated by google. Still no luck. TIA