I'm vegan and let me tell you it can be a challenge
Sometimes appetizers are your friends but sometimes not. Most places will have a salad or can custom make a salad.
When I travel, I always make sure I stay in a hotel with a fridge and buy my own food for breakfast and some dinners if I don't have to go out with others. If I go out with others, I scope out places and customize like crazy.
For instance, for me, at Bertucci's my options would be (I've never been but looked at the menu)
-Antipasto Misto minus prosciutto and mozarella with the dressing on the side
-Tuscan minestrone soup
-Roasted tuscan vegetables (this would be good topping some salad greens)
-Individual pizza, no cheese, lots of veggies
-Portabello sandwich, no mayo, no cheese
Also, you might have to ask for your veggies with no butter but that seems less an issue at italian restaurants than others as olive oil is used more frequently. You might have to ask for them to go light on the oil though.