Tough question but lets think here a bit.
First of all, you do qualify for the Vice President nomination which at one point was often used for candidates in situations like yours.
That said, for state/district noms, I would say that you need to look at HOW you got your US citizenship. If you were born to non-US citizens while travelling/working in the US, your parent (s) would have been in a state even temporarily and I'd try that particular district/state and communicate with the appropriate officials. If you were born outside the US to US citizen parents, it is actually easier as you would use the district/state where they are/were a resident and communicate with those officials. Even if they live permanently outside of the US, the place where they WERE a resident (hopefully registered to vote, etc).
In my opinion, if you are age 18 or older, the FIRST THING to do is to register to vote in the appropriate district which will at least start a residency claim.