Go to the PSN (PlayStation Network) store, and buy him!
Complete the game to unlock Arena mode under the extras option.
Unlockable: New Goblin
You must beat him in your first encounter with him. Using a unique locomotion system that's entirely controllable with the SIXAXIS gamepad, the New Goblin is be able to zip through the city streets and between skyscrapers and other buildings. You must do this In the Collecters Edition of Spider Man 3.
Defeat Venom at the grand finale mission to get the Black Spiderman Suit as a unlockable.
Unlock New Goblin – Defeat New Goblin in the Collector's Edition version of the game.
This cheat is useful if you want to abuse webzip to either get places a little faster, or use it in places you normally cannot.
Once you have completed one successful web zip in the air, you can continue web-zipping for an extended period of time, without actually having to attach your web anywhere.
Simply continue pressing R2 (Web Zip) over and over, and Spidey will glitch, and continue web-zipping.
However, you can't use this infinitely, as he'll slowly be descending down to the ground as you do this.
I hope someone finds this useful/cool.