I ran a diary on my recent honeymoon to Tuscany/Rome, please feel free to take a look, link in my signature below.
Highlights:
1. I recommend driving through the countryside, roads and directions are relatively easy to follow [get a good map before you go and study possible routes]. Do not under any circumstances drive into Rome... you might die.
2. Highly recommend Montepulciano... great town, great scenery, great wine.
3. Many wineries were closed on Wednesday, plan ahead and see when they're open so you're not upset when you get to a region and find out everything's closed on whatever day.
4. Tuscan towns I didn't get to see that I will on my next trip: San Gimignano, Siena, Monteriggioni, Montalcino, Scansano, Assisi [Umbria].
5. I also highly recommend renting a villa in one location for the time you're there [surprisingly affordable if that's an issue] in a city off the tourist's map [we stayed in Montepulciano]. It was one of the highlights of our trip, being able to sit at our villa and relax nightly.
6. We went in early November, weather was beautiful, slightly cool, and less tourists.
7. Pick a region and stick to it... there's plenty to see everywhere you go... you don't want to overload yourself by doing Piedmont and Tuscany and Umbria and the Amalfi.
8. If you have anything shipped back to the US, make sure you get the shipping costs up front. We were taken to the cleaners by a ceramic dealer that charged us about $250 to ship a box with two ceramic bowls in it [in contrast a case of wine cost us $130].
Sorry about the long list but I keep on coming up with tips.