HELP – DATA RECOVERY

HI, major problem… User had a major problem, and only way to fix was to re-install XP..
So loaded a ghost image, only forgot 1 thing, they had their Outlook PST file in a different folder form where other data was copied from.. It is critical data.

What is the simplest way to get the data back? Knowing that i have already installed office again on the image before realising the PST file was lost.
Help would be appreciated