Hi, we are Silvia and Bio and we are "native Italians". We got a web site about italian slang, dialect, proverbs and anything else that you would not find on a normal dictionary: www.stradizionario.it. At the moment it's a bit plain, but it's growing and I someone may find it useful.... If you go to http://www.stradizionario.it/segnala.php you can upload new words and phrases.
Our stradizionario is quite young and it would be very helpful for us if you can tell us about things you would like to know and that you can't find (by going to http://www.stradizionario.it/contatti.php). We are open to any suggestion.
Grazie mille! Ciao ciao da Silvia e Bio