LDAP is the system database which contains all the user information and not configuration files. Therefore would have to edit the databse to change the paths
Can't you just mount /home to another location? why do you want to move it - space constraints?
For another drive...If you edit /etc/fstab and create a line (this example mounts the /home directory to another drive partition sdb1).
/dev/sdb1 /home ext3 defaults 0 0
You can then copy (or move) your data from your old location to the new one
If you want to keep /home on the same drive then mount bind should do what you want. The line in /etc/fstab becomes something like:-
/home /path/to/directory/home none bind,rw 0 0