Question : how to "ping" a MAC address

I have an old printer which was setup on the network before.  Some "fool" though has not labelled it so I do not know it's reserved IP, and network name.  When I go to reserve a new IP for it in DHCP I get the message saying that the client is already reserved (I believe it means the MAC address).  How do I do a search on the MAC address to find the reserved IP and name for it?
Thanks,

Answer : how to "ping" a MAC address

Have you tried to install the JetAdmin software from HP (free download) and let it try to find your pronter on the network (select IP is the protocol of choice)? It should show you the current settings, including current IP address.