You can follow them here.
I also contacted them via their website and got this reply: “We appreciate your interest in the iQ and apologize this vehicle is not available in the U.S. Your comments and interest in this vehicle have been documented at our National Headquarters, where they remain available for review from the appropriate departments.” Sounds kind of form-letter-ish, but if it’s at all possible that some Toyota bureaucrat will actually read my message, I’m encouraged.
My message: “You should: a) Bring the iQ to the USA; b) Do a Fiestamovement thing; and c) Let me be a test driver. Thanks.”