So right now a Coinbase listing is still pending for US investors. Once it gets listed on Coinbase the price is going to explode. Right now you can currently buy it on Binance (the Mega Chinese exchange) if you have an old grandfathered in account. Newer Binance accounts do not allow USA account holders to purchase Theta or Tfuel. The Binance account I created in 2017 did allow me to purchase.

There is another way though and I can vouch for it as I have used it several times and thats with a site called Simpleswap.io

What you do is you buy BTC or ETH, whatever you have access to (they pretty much will swap anything) and you use that to swap for Theta or Tfuel. You'll need to go to Thetatoken.org first and set up your wallet so you can receive the tokens from simpleswap. You can have the Theta web wallet or you can set it up with your Ledger or Trezor hardware wallet. Which is really nice, I have a ledger and love it. (cold storage FTW)

Back in June or July Coinbase had announced Theta was on their "to get listed list" so it can happen anytime. Once it does most are thinking the price will double or triple overnight. So kudos to all of you that are going to grab this before that happens :)

Here's a video on how to use SimpleSwap's mobile app, they have a Website as well for PC.