You can use the command ipconfig. To do this, go to "start menu" and choose "Run", typing in the field cmd. The console window appears black, it should type the command ipconfig/all. After that, the on-screen text looking for "local area Connection" (Ethernet adapter). The string "Physical address" and will represent the desired MAC address. If one computer has multiple network cards, the physical addresses in the list respectively, will also be several, one for each installed card. It is therefore necessary to select from the list the address of the card, which you are currently interested in.
There is another way of determining the network address of the computer that are considered the most effective, but at the same time very popular and commonplace. He is to use two commands - ping and arp. In this case, it first performs a ping target, and then the arp–a command. After executing this command, you will see a table. It will contain the MAC address of the adapter that you are interested in. This method is most commonly used in a conventional peer-to-peer network. The fact is that if the network is segmented and uses the routers to find the MAC address of the computer to learn will not work (will only know the network address of the router).