Problems with transmission

I have a 2wire router/modem and Im trying to open ports. I use oink and need to open ports to upload and keep my ratio. I am new to mac and Im trying to figure out what the name of my computer is on the network so I can tell in my router? How do I find this out?

 

System Preferences->Sharing will allow you to set the name of the computer and to be able to see the name as it looks to other computers on your subnet.