1.

(probably most of you already know it?)
2.

Both of them offer the keys or a account with the game. Heres a tut on how to use the account ! (

You can get different keys there (Steam, xbl etc.) and all for a very cheap price.
If you got other sites too just post them here please.
Hope youŽll like it !
You can add me on psn @ PochinoDelyana