Best website to book train tickets in Italy

If you can get registered properly, the best site to use is the Italian national rail website, at http://www.trenitalia.com/en/index.html . Go there first to register, then await the e-mail password you will get. ASAP after you receive that password, log in and change it to something you can recognize. Then you should be able to go in and purchase. Many Americans have reported problems using their credit cards, but Canadian cards seem to be exempt from that issue. If you know your travel dates, you can book Amica fares, which are 20% off regular fares. And unless there's some special need, take second class. First class, IMHO, isn't worth the extra cost. You should be able to book your tickets up to 60 days in advance of your travel.

Regarding Trenitalia, a number of people have mentioned problems with US credit cards when booking, and I too have had that problem on occasion. I did write to them once and they told me if you use one card and it doesn't work, then you turnaround and try to book again with a different card, it locks you out. Then you have to write to them to get reinstated, or perhaps wait a certain number of days until you can book again. I really don't know why sometimes there are problems, there doesn't seem to be any rhyme or reason. I like their site, its just frustrating when you can't get your credit card to take. Ditto on the Amica fares.