Network printers are done on a user basis. One thing you could do to find printers which are network and visible to all users is check
HKU\.DEFAULT\Software\Microsoft\Windows NT\CurrentVersion\Devices
and
HKU\.DEFAULT\Software\Microsoft\Windows NT\CurrentVersion\PrinterPorts
To determine the default (probably not set on your Default user) look at Device and DeviceOld under user\Printers