On Windows 7:
C:\Users\user.DOMAIN\AppData\Roaming\Microsoft\Network\Connections\Pbk\rasphone
.pbk
Or
If set up for all users.
C:\ProgramData\Microsoft\Network\Connections\Pbk\rasphone.pbk
Rasphone.pbk appears to be the repository of vpn connections. It is a text
file.
On Server 2003 it is located in...
C:\Documents and Settings\All Users\Application
Data\Microsoft\Network\Connections\Pbk