I've addressed this to almost everyone who has asked me such. Even some who don't.
God "having a creator" (even if it is Himself) is not a rational that we can venture to. Not saying one we shouldn't, but one we CANT.
Given that Time is a property of the Universe, and God created the Universe, God gave the Universe the Time. Thus "before" God does not exist in any way we could fathom. If there is no "before" there is no "creator"
Thus, God has always been. End of story.
----If a god created a musician then a god created him. If a god created a musician but did not have any control over what the musician would end up doing, then he is a limited god. I already discussed limited gods above.----
What if God wasn't within the realm of thinking as we perceive 'life', as in being 'created' by something. We are subject to creation, I believe that God doesn't exist in the way we look inwards within ourselves. Creation is an instrument created by God, that doesn't necessarily mean creation applies to God.