Lego Batman

Im only in the beginning part of the game but last time i checked theres a area on the first floor of the batcave where you walk into an elevator and it takes you to a library where all your creations sit on shelves

Ok, I can't speak for the other consoles of the game as to where exactly to find it, but on the PSP you've first got to complete one of the first three episodes (Riddler, Penguin, or Joker, all five missions in one of these). This then opens up the villian levels of that episode which can only be accessed from Arkham Asylum. Go all the way to the left side from the main section of the Batcave (the garage area, you want to go past the Batmobile because if you go past the Batwing you're heading for the library/trophy room in Wayne Manor). Ride the elevator up to the area where you've got the Batcomputer. This area includes change costumes for Batman, Robin, Nightwing, and Batgirl (Nightwing wear's Robin's costumes and Batgirl wears Batmans), the main computer where you can purchase new things or enter codes), a couple search lights, and on the far right side a computer that lets you "check" on the villians at Arkham. Go all the way to the far right and flip the switch to enter Arkham, youll switch to a couple of the super villians (I'm guessing it's probably the boss and their first hench-partner cause I finished the Riddler episode first and every time I enter Arkham it's as Riddler and Clayface). Go to the right out of this area (let's call it the Arkham computer and pit room) until you reach two doors. One leads to the Arkham trophy room, the other leads to the character creator. If memory serves it's the second door, the one closest to the edge of the screen. Take it and go past three cells before reaching the room with the character creator (at least on the PSP you'll know you're going the right way if the hallway has three cells in it).