To find the MAC address on a PC running Windows XP:

Go to Run and type in

    cmd

and push the enter key.  A black window will come up.  At the cursor, type

    ipconfig  /all

and push the enter key.  The MAC address is the physical address for the wireless adapter.

Note that our WEP key is 128-bit.  Most wireless cards can accept a 128-bit ASCII WEP,
but some require that you enter hexadecimal.  Do not enter the WEP in a space marked
"pass phrase" - it doesn't work.

Mac - http://coffer.com/mac_info/locate-macintosh.html

Unix, Solaris, etc. - http://www-dcn.fnal.gov/DCG-Docs/mac/