-login into your router by typing the ip address of your router into Internet Explorer or Firefox
The default setting for Linksys is http://192.168.1.1/
-login with your administrator password
-go to "status" tab
-then go to the "local network" mini tab
-click on the "dhcp client table" and you will see the computers that are using dhcp
There are other ways to do this, but this is pry the easiest