Or, if you would rather get the last portion of the OU tree you could use something like this...

 Code:
$OU = GetObject("LDAP://"+CreateObject("ADSystemInfo").ComputerName).Parent
$OU = Split(Right($OU,-InStrRev($OU,"OU=")-2),",")[0]

If $OU = "OUName1"
   $nul = AddPrinterConnection("\\Server\Printer1")
   $nul = AddPrinterConnection("\\Server\Printer2")
Endif
If $OU = "OUName2"
   $nul = AddPrinterConnection("\\Server\Printer3")
   $nul = AddPrinterConnection("\\Server\Printer4")
Endif