Outlook 2000, 2002 & 2003 default PST file location in Windows Vista and above OS is:
C:\Users\UserName\AppData\Local\Microsoft\Outlook
Outlook 2000, 2002 & 2003 default PST file location in Windows XP & older version is:
C:\Documents and Settings\UserName\AppData\Local\Microsoft\Outlook
Username: Is the login account name used in your computer.