I just purchased electronic tickets on Trenitalia today for a trip we are taking in June. I was able to purchase super economy fares (which are non-refundable and non-changable) for a same day round trip Roma Termini-Firenze Santa Maria Novella and a one way from Roma Termini to Napoli Centrale. I chose automatic seat assignment to put the four of us together. I did not have to register (I checked non sono registrato) and I was able to use my US Master Card. I called Capital One first to let them know I was going to make an online purchase at Trenitalia website using euro currency. There are no foreign transaction fees with Capital One. I also provided my .net email address (not a .com) and received a confirmation email in my inbox in less than a minute. The confirmation included my booking code, master code and ticket code with a pdf to print out and show to the conductor once we are already onboard, no validation needed. I would think that I could also show them the email confirmation on my iphone as proof of purchase. I hope this clears up any confusion. Happy travels!