You can check the default location for those files here:
http://www.slipstick.com/config/backup.htm

Signature
Russ Valentine
[MVP-Outlook]
> Hello,
>
> One of our users lost her hard drive, but no worries I have a week old CD backup of her 'documents and settings.' On that CD backup I have a folder
named C:\Documents and Settings\default\Application Data\Microsoft\Outlook\.
However, of the 21 files contained within that folder, none are a .pst file.
There are however .FAV .NK2 .SRS and .DAT files. A search of the 'documents
and settings' reveals 74 .pst files in her 'My Documents' folder containing
topic-related archived e-mail and previously sent and archived e-mail, but
all with user-generated names other than 'outlook.pst'
> At this point, do I have to conclude that her .pst file was moved by someone at sometime to a different location and thus have no hope of
recreating her contacts information?
> She is using Outlook 2002 on Windows XP version 5.1.
>
> Thank you in advance for your reply,
> MWilson