are you looking for a complete bike, or just a frame? i think pretty much any lugged frame is "timeless," whether it stays that way is a matter of the build. a frame built with chrome parts, low profile rims, traditional track drops, leather saddle will look quite timeless. the exact same frame built up with risers, a messenger ring, deep v's and a pink chain will not.
what is it about Italian brands that get you excited? is it the name? i hope you don't think that all italian brands are made in italy. bianchi sure isn't. colnago and de rosa are i know. most brands today, the frames are made in asia, with only the final bike being assembled in it's respective country (sometimes not even then).
however, if you are sifting through ebay, the shift to asia is only something that has been going on in the past 20-30 years, so finding nice italian frames from the 70's-80's or earlier are pretty much guaranteed to have been built in italy. hope that helps.