Hey bud, congrats on going through the hunter ed course! I consider myself quite at home with shotguns, I've been shooting them since I was 10 years old.
What do you intend to hunt with the shotgun? I think is very important, because while there are some "universal" shotguns, there are much better guns for different things.
For example, if you intend to hunt deer with a shotgun, I'd recommend a 20 guage with rifled slug barrel 22-24". I've killed deer at 100 yards easily with my 20ga. slug gun, but that's all this gun is used for.
For upland, I shoot a Browning Gold Hunter 12ga. chambered for 3" with a 28" barrel. Soft recoil allows quick target re-acquisition after a shot and believe it or not, the 28" barrel forces you to slow down you swing and overall "slows down" the shooting process, which allows for better shot placement. Many a pheasant and quail have fallen to that Browning Gold. Beautiful gun for upland and for skeet shooting.
Now for waterfowl hunting, which is my self-declared speciality, I pull out all the stops. Because hunting conditions are near/over water and typically in wet, cold weather, many shotguns would leave you burned on these days. I think duck hunting can present the most difficult weather conditions for a shotgun. While a Remington 870 pump will never let you down, a Benelli shotgun will not only never let you down, but it will drop ducks like rain.
I own 2 Benelli shotguns - an M1 field and a SBEII. The M1 was a sweet deal I purchased new the last year they made them. $850 out the door - brand new. The SBEII I just got a couple years ago for $1300. Between the two, the M1 is my go to machine for dropping waterfowl. She's a 12ga. with a 26" barrel and patternmaster waterfowl choke. Any duck inside 50 yards is in serious trouble with this weapon.
I live and waterfowl hunt in New Jersey along the Jersey coast. Last season I hunted in many snow storms, but one in particular stood out. Was hunting with my brother, who also has a Browning Gold Hunter. Conditions were horrible, visibility less than 1/4 mile in heavy snow. Ducks were just pouring into the decoys. My brothers browning actually had a few cycle jams (due to the cold weather, gas operated guns will operate slower). My M1 on the other hand, was knocking birds down all morning and never skipped a beat.
So you really need to think about what you're going to be doing with the gun. If its mostly target/upland, I would definitely look at the Browning Gold series. They are affordable and I absolutely love my Gold hunter for upland and target.
If you're going to be duck hunting, I'd definitely look at the Benelli line. Most reliable and durable shotguns in my opinion.