Hi Julietta, IMHO the possibility to know persons speaking in italian is equal everywhere! Of course, the large use of local dialects is incredible above all with young slangy guys and more humble people (in some context [incredible... no comment] it's not considerated "polite" to use the dialect), and in some part of italy you'll easily listen to a mixture of both, for everykind and age of persons you'll met. So you have the same occasions so listen and speak in "classical" italian in milano, venezia, rome, catania, bologna, firenze.... but even if you'll hear to "classical italian" be sure that every region has is own intonations that you'll love to hear and recognize :D Pure classical italian in form and intonation should be the one that only persons like actors/actress, radio/tv presenters which study "DIZIONE" (Modo chiaro e corretto di pronunciare le parole). But it's not so common... :D Plan well your travel!!! For any help ask!

Come to Tuscany... However, because of the large spread of dialects and different pronunciations, maybe you better watch some Italian or translated-to-Italian movies (these last are surely correct in language, while the local ones sometimes use dialects), as well as trying to listen to some radio programmes. Pure correct Italian is neither common or unusual, it just depends on how much people want to talk correctly and try to. I really think it's more frequent in central Italy than in the North or South – some extreme dialects completely sound as other languages!