Are you referring to a user that has been created, but does not currently have a home directory? It's generally best to use the -d flag in useradd to automatically create the user's home directory when the user is added.
Anyway, you should be able to make the directory as root with a simple mkdir and setting the appropriate permissions (700, user:group). You may also want to copy in some dummy initialization scripts as well to give the user something to work off of (.bashrc, .bash_profile, etc.).
Last edited by suicidaleggroll; 02-07-2013 at 06:50 PM.