Traditional Italian dances are hard to find in Italy in general. The top three are the tarantella from Puglia, the Sardinian ballu tundu (round dance) and the Neapolitan Saltarello. If you want to dance anywhere that's not a disco, you're best off looking for latin dancing, which is very popular all over Italy and there are plenty of places to learn or just dance the Tango, cha cha, Mumba etc. Also, ballroom dancing is very popular. In general you won't find much folk dancing in the bigger cities but in country towns, or in Southern Italy.
The top ten Italian singers are:
Modern or pop Italian groups
... but they are two separate lists of 10 for different things :-)
not very good if you see the 101 it is 20