Sicily

Italian trains are relatively cheap, so a train pass is rarely a good deal. And that's the "base" fare (full fare, such as tickets bought at the last minute). If you buy in advance online, and can commit to tickets that cannot be refunded or exchanged (or have significant restrictions on these actions), you can save a lot. To look at train prices, use the Trenitalia website, following Ron In Rome's detailed directions: http://tinyurl.com/c4t693b.

I don't know what a "one week" train ticket is. If you intended to say "one way" ticket the answer is yes. You can buy either one way or return ticket anyplace.

Martin / Lorraine, I've never heard of a "one week train ticket", so I doubt it. How many rail trips are you planning on taking? P-P tickets are usually quite cheap, so that's often the best option. I doubt that a Railpass would be cost effective. Happy travels!