If you move the main PST and start Outlook, Outlook will prompt you for the
location, allowing you to browse to the new folder where you stored it.
If we are not talking about mail .pst file then there is a hidden
problem - if you have Outlook setup to archive items to that .pst file
(which was moved) simply pointing to new location of the file will not
solve the issue without additional problems. Whenever archiving will
take place Outlook will create new .pst file in old location so you'll
have two files now. You can update your rule (default AutoArchive
option) with new location of the file - then the issue described will
not take place.
On other hand sometimes movind main .pst file ruins Outlook so it will
not start (as said in top post). I do not know solution for this
problem as showing new location or recreating account will not help. I
found that the only way to fix it is to create new user profile (just
to add new user and delete old one) and later to attach existing file
to your Outlook as second (backup) file. If any other solution is
known - please share.