Hey Martlet,
From one North Shore bird hunting fanatic and shotgun enthusiast to another:
I've purchased two shotguns recently: a Benelli SuperNova and a B. Rizzini Omnium over/under. I've spent many hours in the field with each gun at this point and love them both for different reasons.
The Benelli Supernova is my no-frills, all-purpose hunting shotgun. While searching for the right 12 gauge pump I tried them all: Remington, Mossberg, Browning. The Supernova came out ahead for lots of reasons: chrome lined barrel, ability to eject the chambered round without loading a round into the chamber from the mag, adjustable cast and drop, location of the action release and safety, synthetic receiver, short stroke pump, ability to field strip in a few seconds without tools and overall fit and finish. It's a cheap, rugged 12 gauge that patterns beautifully and works every time. I use it primarily for turkey, though on really rainy days it will join me out in the field while upland hunting. They make great deer guns too, though I'm primarily a bird hunter. If you get one, pay a little extra for a camo dipped one. They're ugly, but the dip basically makes the gun weather-proof.
The 20 gauge B. Rizzini is my partridge/woodcock gun. If you've never shot an over/under I highly recommend trying one. There is nothing like it. Yes, you are limited to two shots, but the handling characteristics of a good O/U simply can't be beat. They are snappy, light and point naturally. They also give you the ability to employ two chokes simultaneously. Using your barrel selector, you can choose which kind of choke you want to use instantly depending on field conditions. Or if you miss on your first shot, your second barrel is choked tighter for a farther follow-up. They are simple to maintain, and if you get a good one you will be very hard pressed to ever wear it down. They also give you a generally shorter overall gun length than a comparable pump or semi-auto because the receivers are so short. Compare a 28" O/U to a 28" Montefeltro and you'll see what I mean: the Monetfeltro will feel extremely long and ungainly.
My brother hunts with a 20 gauge Ruger Red Label O/U and loves it. I shot it and thought it was a very fine shotgun for the money. I believe he paid 1200 for it. It is heavier than its Italian counterparts, but you save a lot of money. The Berettas are nice, as are the Caesar Guerini's. I prefer Rizzini to both Beretta and Guerini, but it really comes down to personal preference as they are all wonderful shotguns. Expect to pay 1600-2000 for a good, entry level Italian double.
These are my thoughts after spendling lots of time looking for the right bird guns. You might consider heading over to the River's Edge Trading Company in Beverly, MA. I bought my Rizzini there, and David had some other really choice pieces. His selection is small, but very high quality. There is a Rizzini made Sig Arms/LL. Bean "New Englander" 20 gauge there that is gorgeous. I believe it's 1900. It would be a fantastic bird gun.
Good luck!