MS Outlook Data file (*.pst) location in NTUSER.DAT
HKEY_CURRENT_USER\Software\Microsoft\Office\[versionNumber]\Outlook\Catalog
Sample:
MS Outlook 2007
HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\Catalog
MS Outlook 2010
HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Search
HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Search\Catalog
Other Location:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\ComDlg32\OpenSaveMRU\PST
