How do you find you mac address on pc?

go to the command prompt and type ipconfig

On Windows XP you can
Open a command promt and type:
getmac

The MAC address will be noted on the column on the left under "Physical Address"
This will show you the MAC of all of your enabled network adapters

You also can try ipconfig /all

do
DOS command

ipconfig/all

The MAC address can be found by following these steps
1) select run and type "Cmd" ( windows 2000 upwards) or "command" ( win 98 downwards)
2) type "ipconfig /all"
3) Your MAC address(es) will be displayed.( you can have more than one .. one each for say your modem, LAN card , etc)
Optional step ( if more than one address shown)
4) find the paragraph in the results that starts with "Ethernet" or "Internet" and use the MAC address mentioned there

Phone up your ISP and they'll tell you.

Identifying your MAC address is easy. In most cases, it is physically printed on the adapter itself. On a laptop with a PC Card-based adapter this is easy to see. Just disconnect the card and flip it over. On a PC or a laptop with an integrated network adapter you'll need to find the MAC address using software. The process is almost identical to the utility you use to see your system's IP address. On a Windows 2000 or Windows XP machine that would be IPCONFIG.