Well I got married in Siracusa, Sicilia, but we were more local, though we had to plan some of it long distance as my wife moved to near Venice to take a better position and I left Germany and went to the States for about a year. We did not use a planner but you can expect everything to get more expensive when you mention "wedding" just like in the States.
The best part for us was going to the different villas for the tastings, we got ~7 free meals :-)

We had a great Villa in the fringe of Siracusa with a nice view and great food served and cooked there. Our local families took the visitors to the villa from the cathedral while we did pics. For the food we paid ~60 euros a plate which was a special as there was some form of relation. the normal price for ours was 85 euros. meal included antipasti table outside, two first courses, fish, third course, sides with the second fish dish, sorbetto and wedding cake and dessert buffet and champagne and wine included. We had ~120 guests.

IN Sicily is was not bad doing it ourselves, but again we were "local" and not paying hotel fees and such. I have seen adverts for English speaking planners. No idea how much they cost. I'll see if I can find any. Transport to Sicily from the states normally requires a connection (save a seasonal Palermo NYC flight) Catania is a bigger overall airport. That can be the biggest hurdle for some though there are various non-stops to the big Euro cities, CDG, FRA, mUC, LGW etc

Good luck! Let me know maybe I can answer specific questions.

Ciao,
FH