Just remember that things are very different in Italy from the North America (as well as Great Britain and Australia, I assume), so don't expect a minimum wage, or even any sort of legal contract. Bartender jobs, etc will probably not pay more than 5 euros an hour. However, you're drinking for free, so maybe it evens out in the end.
If you're considering it, the first place to look is Wanted in Rome, an English-language website devoted to those of us living and studying in Rome. Check it out, but just be wary, as always, of those trying to take advantage.