You can use the Network Utility application to find the MAC address on your computer.
Every computer device that is capable of connecting to the Internet has a unique hardware address, known as the the Media Access Control address, or MAC address. If you are using the Mac OS X 10.5 operating system, known as Leopard, you can find your computer's MAC address by using the Network Utility tool. Computers with multiple network adapters, like Ethernet and wireless, will have a separate MAC address for each adapter.
Instructions
1. Click on the "Finder" icon in the dock to open a new Finder window.
2. Go to the "Applications" section from the "Places" list on the left side of the Finder window.
3. Open the "Utilities" folder and double-click on the icon labeled "Network Utility."
4. Go to the "Info" tab at the top of the Network Utility window.
5. Open the "Network interface" drop-down menu and select the adapter you want to view.
6. Look in the "Hardware Address" field under the "Interface Information" section to find the MAC address for the network adapter you selected.
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