If you have the time, head up to the Shelburne Museum on Rt. 7 just south of Burlington. It has a collection of early American waterfowl hunting decoys that is billed (pun intended) as the most comprehensive collection in the country. The museum has more than 900 decoys and carvers include Elmer Crowell, Shang Wheeler, Gus Wilson, Bill Bowman, Joseph Lincoln, Lee Dudley, George Warin and John Blair. Decoys from Maine, Massachusetts, Long Island, Chesapeake Bay, Illinois, Quebec and other regions are exhibited, and there's some neat items from the old market hunting days.
There's also a lot more to see if you like folk art and early Americana. The museum itself is very unusual. It is not one or two big buildings. Instead, it consists of more than a dozen original 18th, 19th and early 20th century buildings (and one paddlewheel steamboat) that have been carefully relocated to the museum's grounds. They include an old lighthouse, a round barn, a general store and apothecary, and an old schoolhouse, among other things. Each building houses one or more collections.
Although not duck related, the museum's Beach Lodge and Gallery is pretty cool if you like to hunt. The Lodge is an old Adirondack hunting camp and it is full of trophy big-game heads and full-body mounts, some of which were taken by museum founders Electra Havemeyer Webb and her husband James Watson Webb, who also helped develop the B&C big-game scoring system. The gallery is devoted to wildlife-related paintings, prints and bronzes by artists like Carl Rungius, Arthur Fitzwilliam Tait and Sydney Laurence. Last year it also hosted a collection of 18th and 19th century guns made in Vermont.
I also like the Ogden Pleissner Gallery, which includes a re-creation of the famous painter's Manchester, Vermont, studio as it was on the day of his death, right down to his favorite bird gun leaning against the wall.
I highly recommend it. You can learn more at shelburnemuseum.org.
If you're more interested in fly fishing, however, head south to Manchester, where you can visit Orvis' main retail store and rod-making shop, and the nearby American Museum of Fly Fishing.
Finally, if you want to blend in with all the clueless, knucklehead tourists that descend on Vermont, you can visit Ben & Jerry's main facility in Waterbury and buy a tie-dyed T-shirt. (The ice cream is great, but the rest of the trappings I can live without.)