I'm having trouble signing into multiple accounts on my PS3 locally. I want to assign each controller/player their account, but the game is not allowing to me do so, like on the 360. Whenever I connect a controller to the console and press X to join, it joins, but it gives the first account to that controller and adds a number to the end (i.e. Player1(2)). How do I sign into multiple accounts for offline multiplayer?
Unfortunately, you cannot sign into multiple accounts at once on the PS3. Any user aside from the currently logged in player will just be Player 2/3/4. From here:
Only one user may sign into their account on PlayStation 3, PSP, PS TV or PS Vita systems at any one time.
For offline multiplayer in Black Ops there's no option like for Modern Warfare.
On the Modern Warfare series you can create profiles that go into the account's save file of the game. That way you can customize everything and even level up on each profile, save them, and use them again anytime the owner of the profile, play again (on the same PS account's save file of the game). Black Ops does not have this option. However...
For Online multiplayer in Black Ops 2 you do can use another PS account. When you go online and another joins in on the same console, it gives you the option to use another PS account or to create a profile.
For Offline multiplayer on PS3, none of the Call Of Duty games (or any other series that I'm aware of) let you use another PS account (only profiles on some) like in the Xbox. Not sure about PS4