Cisco Switch: Find out an IP from MAC address

1. sh mac-adress table int f0/x
,where x is the port number.
2. log into the default gatway router
3 sh ip arp xxxx.xxxx.xxxx
, where xxxx.xxxx.xxxx is the MAC address

If you have the MAC already, skip #1.

Reference:
Cisco - Find out an IP from MAC address on CAtalyst 2950
http://www.velocityreviews.com/forums/t39860-find-out-an-ip-from-mac-address-on-catalyst-2950-a.html