distribution certificate

guys help me!!
I just finished my application I want to publish, but I realized that you have all certificates except the distribution certificate (required for export p12)
How do I create a distribution certificate??

I believe this is covered in Help > Stencylpedia

Here:
http://www.stencyl.com/help/view/publish-to-app-store/
It´s quite a task if you are not yet a registered Apple developer. But doable.