Instructions
Load the game disc on your PS3 and select "Multiplayer" from the "Call of Duty: Black Ops" main menu.
Select "Live" from the Multiplayer menu and choose "Player Match."
Click on "Playercard" in the Player Match menu and select "Clan Tag."
Choose "Edit Clan Tag" from the Clan Tag menu and type in a new, four-character clan tag.
Select "Done" and press "Back" twice to return to the Player Match menu. You are now ready to join a "Call of Duty: Black Ops" multiplayer match on your PS3 with your newly modified clan tag.