Using NETDOM.EXE from the Support Tools folder of your Server Operating System CD-ROM, I have scripted DHCPND.bat to determine what non-domain computers on your network have IP addresses that are in the scope(s) of your domain's DHCP server.

The syntax for using DHCPND.bat is:

DHCPND DomainName Scope123 Scope4S Scope4E \[NextScope123 NextScope4S NextScope4E .....\]

where:

DomainName    is the your NetBIOS or fully qualified domain name.

Scope123      is the first 3 octets of a scope, like 192.168.0.

Scope4S       is the lowest value of the fourth octet that you want checked.

Scope4E       is the highest value of the fourth octet that you want checked.

NextScope123  and NextScope4S and NextScope4E are optional addition scopes. 
              There is no limit to the number of optional parameters.

Examples:

dhcp jsiinc 192.168.0 1 9 192.168.0 50 79         This is one scope, but I excluded 192.168.0.10 - 192.168.0.49 and
                                                  addresses greater than 192.168.0.79.

dhcp jsiinc.com 123.10.1 0 254 123.11.0 0 254     This is two full scopes.

NOTE: DHCPND.bat displays its' output on the console.

NOTE: Ping is used to locate the computers. If a computer is powered off, it will NOT be found. If your scope contains unused addresses, Ping has to time out, increasing the run time.

DHCPND.bat contains:

@echo off
if \{%4\}
\{\} @echo Syntax: DHCPND DomainName Scope123 Scope4S Scope4E \[NextScope123 NextScope4S NextScope4E .....\]&goto :EOF
setlocal
set domain=%1
if exist %temp%\DHCPND.tmp del /q %temp%\DHCPND.tmp
for /f "Skip=1 Tokens=1" %%c in ('netdom query /domain:%domain% workstation') do if /i "%%c" NEQ "The" @echo %%c>>%temp%\DHCPND.tmp
for /f "Skip=1 Tokens=1" %%c in ('netdom query /domain:%domain% server') do if /i "%%c" NEQ "The" @echo %%c>>%temp%\DHCPND.tmp
for /f "Skip=1 Tokens=1" %%c in ('netdom query /domain:%domain% DC') do if /i "%%c" NEQ "The" @echo %%c>>%temp%\DHCPND.tmp
:more
if \{%2\}
\{\} goto Finish
set oct123=%2#
set oct123=%oct123:.#=%
set oct123=%oct123:#=%
for /l %%i in (%3,1,%4) do (
 for /f "Tokens=1,2* Delims=. " %%p in ('ping -a -n 1 %oct123%.%%i') do if "%%p" EQU "Pinging" set computer=%%q&set stuff=%%r&call :find
)
shift
shift
shift
goto more
:finish
if exist %temp%\DHCPND.tmp del /q %temp%\DHCPND.tmp
endlocal
goto :EOF
:find
set work=%stuff:\[=%
if "%work%" EQU "%stuff%" goto :EOF
set stuff=%stuff: with 32 bytes of data:=%
set OK=Y
for /f "Tokens=*" %%s in ('findstr /i /l /c:"%computer%" %temp%\DHCPND.tmp') do set OK=%computer%.%stuff%
If "%OK%" NEQ "Y" goto :EOF
@echo %computer%.%stuff%