When I saw this:
Out of the blue the interviewer asks me "If you needed to know how many gas stations are in the US, and you only had a short amount of time to research it to give a rough estimate, what would you do? The process of how you find the answer is more important than the final answer. Answer this very quickly."
That is a clue in to the fact that he didn't give a shit about the answer just the process at to which you can come up with one. Not saying you blew it, we've all been there, I bet. I haven't been asked many questions like that, only silly things like, "What are ten things you can use a pencil/pen for, not including writing?" (Ralph Lauren). One of my answers were Draw and the interviewer told me that was funny because his wife answered him with the same answer. Not sure if that helped me or hurt me, job itself got cancelled since the interviewer moved to a new company the next week.
Anyway, Good Luck Reggs, hope you get what you are looking for!