How to change your apple id?

I used a email as my apple id. I made a new email and don't use the one I used for the apple is. How can I switch everything to the new email? My iPhone 4s, iTunes, App Store, Macbook Pro?

As far as I know, it may not be possible. You could contact apple on their support site to see if they can do it for you. I'm really not sure of this though, so if someone knows more about it, feel free to prove me wrong.

Change the name for your main Apple ID at the link below.

That change will not be retroactive. You can't change the Apple ID related to past purchases, only related to the future. From the second link below…
"I have multiple Apple IDs. Is there a way for me to merge them into a single Apple ID?
Apple IDs can't be merged. You should use your preferred Apple ID from now on, but you can still access your purchased items such as music, movies, or software using your other Apple IDs."