For as little as $50 (or as much as $100) you can join a fishing charter from 1000 Islands Fishing Charters company. They provide rods, reels, bait, boat and take you out in the St. Lawrence River to try and catch musky, pike, walleye.
Your actual cost depends on the number of people available for the charter (more people means lower cost per person) and the length of the charter time (four hour minimum) and the amenities (some charters have food and beverages). Call ahead for reservations and details on each charter (or take a look at their website).
For those who are big eaters (and have a few extra bucks to spend), you can add an afternoon lunch on the shore of the islands. Fresh fish is cooked on an open fire, thousand island dressing is used on fresh greens and corn and potatoes bulk out the meal.