The simplest way to find out where your system believes your home directory to be is to take advantage of the fact that cd with no arguments changes to your home directory:

% cd
% pwd
/home/users/deb

% echo $HOME
/home/users/deb

Your home directory is set in your /etc/passwd entry (or equivalent -- Netinfo on Darwin and NIS on Solaris store the same information, for example). There is no actual requirement that all users' home directories be in the same directory. In fact, I've seen systems that have lots of users organize home directories by the first few letters of the username (so my home directory there was /home/d/de/deb).

If you add user accounts using a tool rather than by using vipw and adding them by hand, take a peek at the documentation for your tool. It should tell you both where it wants to put home directories by default and how to change that default should you want to.

-- DJPH

7. Directory Organization		7.3. Access to Directories