– helps you learn and review new vocabulary in a SRS-fashion.
– The free alternative to Rosetta Stone. Personally, I really don't like that system; I can say it doesn't work for me. Most people I've spoken with, though, praise Livemocha for its amazing community.
– Steve Kaufmann's website. The system is great, I love it. The problem is that the UI isn't very user-friendly in my opinion, and it has discouraged me from using this tool at all.
– You post a piece of text in your target language and a native speaker will read it aloud for you. The weak spot is that the community isn't that large yet (it's fairly new, just came out in April) – I wonder why… (be sure to add me as a friend there, so I can try to record stuff for you http://rhinospike.com/profiles/profile/sunyatasattva/
These are just generic websites you could start off with, not focused on any particular language.
After that, you can try http://www.italianpod101.com/
which offers podcasts with dialogues. You know? I heard some lessons and honestly don't like them, but I suggest you would go over a few lessons at least in the beginning, you could get some nice information.
After you have developed the basics, I suggest you to use http://www.sharedtalk.com/
to have casual chats with random people all over the world who speak your target language, and also try to read or listen to some content BY Italians FOR Italians – and you can find plenty of them, depending on your interests you can always ask me to suggest you something.
Hope that helps.