RAIL!

Since you're going in the high season you might consider buying your tics and getting seat resv in advance. Any site will do.

Things like R, ES, and IC describe the type of trains in Italy...R for regional trains, ES for the EuroStar Italy fast national trains, and IC for INtercity expresses....you'll be able to tell which is faster simply by looking at the trenitalia website. I've found many IC's are almost as fast as the ES...but cheaper. Travel 2nd class...cheaper and not much different from first. Some have reported problems with it recently, but if you can navigate it, prices will be a lot cheaper on trenitalia than on RailEurope. I would also suggest booking ASAP.

You don't always need to purchase your tickets in advance, but you do take the chance of standing on a train...the Italians will allow anyone on a train that has a ticket. We stood for 2 hours on our last trip. Not terrible, but a seat would have been nice.

Another option is to take a bus. They are cheaper still, go most places that the train does...and in some cases where a train won't go! Most times the bus station is right next to the train station, so it's really easy. it's the same thing, buy a ticket, validate it (usually on the bus, or with the bus driver!)

So...don't always think train for travel! bus service is really nice, the buses are clean, and we found, not as crowded as the train!

Point-to-point tix, purchased day of travel and sometimes a day or two in advance, have always worked for us( we have been in Italy for several weeks each time, in 2004 and 2006). Ticket machines are fast,easy and can give you info on available trains for your NEXT journey as well as the one you are doing that day.
Advance purchase is only necessary if you will be taking a night train on a popular line or if you want something special that normally sells out.
Buon Viaggi!!!!

I was there last summer, had no trouble buying tix at the station kiosks. We preferred to buy the day before leaving each town and used the kiosks to figure out what times trains were going. Don't worry about memorizing the abbreviations; the kiosk will tell you the travel time, number of connections, and price. Use those to make your decisions. The numbers it gives are based on the type of train (ES, IC, etc) but let it worry about keeping that straight and just pick the schedule & price that works for you.

You will need reservations on the Eurostar and Euro City trains no matter if you are traveling 1st or 2nd class. If you're traveling on other trains 2nd class, your ticket will most likely be "open" (no seat assignment and good on any train for that destination). You can easily get these tickets 1-2 days before travel. Go to the train station and simply get on. We just got back from Italy and that's what we did. In some areas the trains are getting a bit crowded so you may stand on some runs. Still, you can get on.

just a comment about Larry's post -- boarding a train to Naples from Rome we assumed 2nd class was open seating, so we jumped on the first car with the big "2" on the side. To our surprise, before the train left a couple showed up and wanted our seats! Turns out even some 2nd class cars have reserved seats. In fact, I think that more than 50% of the time we were sitting in an assigned seat over 2 weeks of train travel. The moral is look at your ticket and see if it assigns you to a car & seat.

Mike's comment is valid. As I said above, the nicer trains even require seat reservations in 2nd class. Mike also bumped into a situation that I saw at almost every stop on the nicer trains. Some people do not originally sit in their assigned seats. They sit next to friends or other open seats. At each stop, you see this mini-ballet of people boarding and wanting their correct seats. In all situations, the people in the incorrect seats kindly moved. No problems. It's just something we saw along the way.

What is your recommendation for those of us that have RailEurope train passes already and will be taking ES* Trains.

Should we buy reservations through RailEurope now or wait until we get to a train station in Italy? (There are 8 of us traveling.)

Is it cheaper to buy in Italy?