If you have a smartphone, the Google Translate app (iPhone or Android) would be a good place to start, as it is free.

I use free translation/dictionary apps on my Android phone. The apps come in free/paid, as well as online (such as Google translate)/offline versions.

If you don't have mobile internet access and need to use the app away from WIFI coverage, online versions will be useless to you.

However, there are usually tradeoffs. The offline versions are usually dictionary only and the amount of words are limited. The online versions can do translation of sentences using mobile internet. Many free apps are pretty useless. They have so few words.

Just be aware that Google Translate and the like don't always translate correctly.

None of these online tools or apps comes close to a truly decent translation. And how do you plan to use it? That makes a difference. Please don't say you plan to have "conversations" with people this way - no one will have the patience to deal with it. If it's just so you can understand things you're reading, fine. But do be aware that no software-based translation tool can ever be really accurate.

Google translate is actually fairly accurate and "smart" when it comes to Italian. It is certainly easier to translate things using Google than something like a electronic dictionary that gives only individual words. Italians will be extremely forgiving of any "mistakes" you make using an inaccurate phrase or grammar, so go for it! They will encourage you, so ignore the flak you are getting here. Additionally, Italians are quite enthusiastic about smart phones and electronic devices and are generally MUCH better-tempered than people you will encounter on travel message boards, so don't be surprised if you have a lot of fun with your smartphone or device in Italy. You show them yours, they'll show you theirs!

Problem with trying to translate spoken words is that you don't know to spell them. If you are looking to translate menus, then you might also want to pack a book like "Italy Dish by Dish", because menu items can be so peculiar, and they are often in dialect rather than standard Italian.

If you are not traveling with a smart phone, but want a translator so you can look up shopping words like "gloves" or "wine glasses" or" "snow chains", then I suggest that you go to a travel site like Magellan, or even go to Amazon, and look up items and reviews.

Good for you, by the way, for even being interested in communicating in Italian while you are in Italy.

PS: If you do bring a smartphone or other fancy electronic device, just make sure you hang onto it and flash it only at the right people. In places notorious for pickpocketing problems -- the tourist areas of Rome, Napoli/the Amalfi, Florence, Venice, parts of Genoa, Palermo and Bari, and train stations and airports generally -- "smart" devices are very attractive items to thieves.

Another thing. If you want to use your smartphone away from wifi hotspots, and you don't have a local SIM with cheap data plan, data roaming on your SIM will be extremely expensive.