How do I exchange Bitcoin for IOTA? What's the best venue through which to secure IOTA ultimately as my end goal? Since that other company (it seems I cannot name them here) no longer works with US citizens, who do I interface with now?
You can trade with a neighbor that also installed both wallets ;) or use one of the exchanges... The bigger volume the better: https://coinmarketcap.com/currencies/iota/#markets