Subject: Re: Train travel from Rome to Monterosso
Hello Tiffany,

You're going first class and mid-week, and it looks like your best option is to take an InterCity train to La Spezia, which doesn't require a reservation (then a short hop on a regional train to Monterosso); I would think that you'll do fine without a reservation. If you'd like to have a reservation for peace of mind, you shouldn't have any problem getting one (and your tickets at the same time) once you're in Rome. See for schedules.

Andrew Missouri