Sorry, no recco's. I've been to Italy many times, but as yet, not once to the big three (Rome, Venice, Florence).
Frommers have a good online forum that is worth perusing / posting question about restaurants.
(yellow pages aka business directory) isn't comprehensive, but does allow a search for businesses. There's even an option to search in English. Type wine bar / enoteca / vineria / cantina or similar (and Rome or Roma) in and see what you get back. A lot of wine shops in Italy also serve light food and wine by the glass. My experience of these places has been virtually universally favourable, with the food at times outshining the wine.
Also try a websearch for tourist offices, which often have good listings (including wine bars).
Hope this helps