Hi
I'm not sure if this is what you are looking for - but it worked for me.
In httpd.conf I commented out UserDir disable and uncommented UserDir public_html (Apache 2, don't know about 1.3):
QUOTE
<IfModule mod_userdir.c>
#
# UserDir is disabled by default since it can confirm the presence
# of a username on the system (depending on home directory
# permissions).
#
#UserDir disable
#
# To enable requests to /~user/ to serve the user's public_html
# directory, remove the "UserDir disable" line above, and uncomment
# the following line instead:
#
UserDir public_html
</IfModule>
I can now access my sites using
http://ip/~username where username is the user "assigned" to the domain of the site I want to look at. The above assumes the web site is stored in /home/username/public_html
HTH
Geoff