[Lammarite]

How long are you going for? Try and fit in the north of Lake Garda and Verona too if you can. Verona is one of the coolest cities in Italy, especially if you go to the opera.
My best advice for Rome is to go straight to the train station and ask in the special office for finding accommodation. We got a very nice double room in a B&B with A/C for less than bunk beds in a dorm through Lonely Planet. Others in the Q ahead of us were getting really good deals on higher end hotels too. You just tell the girl what budget you have, what you want and where and she gives you your options. Smile at the girl and crack a little joke for her as she gets some really annoying people in there!