Currently Being ModeratedMay 1, 2012 1:39 PM (in response to The hatter)
Hatter is correct. That is the best way.
You can also use Network Utility to Ping the broadcast address for your subnet (2 pings required). This will give you an answer for all devices on the subnet, but will not identify who-is-who. To do that you ping with and without the suspect device.
If your router is 192.168.0.1, with subnet mask 255.255.255.0, the address to use is 192.168.0.255. Send 2 Pings.Mac Pro (Early 2009), Mac OS X (10.6.8), & Server, PPC, & AppleTalk Printers
Currently Being ModeratedMay 1, 2012 3:37 PM (in response to jake1044)
I bought a little app on the itunes store called iNet. It is a handy network tool to discover and keep track of IP address'