All roads lead to Rome, and many of those roads now come with a toll. Roadside services are adequate. Bus tours are well organized as is the affordable rail system. Passes are good for the bus, subway and ferry boats. (Since the ferry boats run like buses.) Traditional gondola rides are available, but hugely expensive! Info centers and currency exchange booths are easily found all over Italy.
IMPORTANT: if you plan to drive take a look at this funny article with video : Driving in Rome and Naples