Walleyes, and sauger (walleyes little cousins) love rivers with rocky, and sandy bottoms. They can be found in lakes (due mostly to stocking programs) but they prefer rivers. This time of year they normally run up stream to spawn when water temps reach 45-50 degrees. They run upstream as far as they can untill water become too shallow, or the path gets blocked by waterfalls or dams. Walleyes then return too deeper water downstream after the spawn. They typically try to stay in water close to 50 degrees. I always do good year round just below dams especially if dam is open and water is flowing. Fishing at night in rocky waters 5ft deep or less cant be beat since walleyes are nocturnal. I like to fish the bottom with nightcrawler, or float a leech just above bottom. If you prefer artificials i'd suggest twist tail jigs in white, chartruse, or yellow. I hope this helps. Good luck on your walleye expidition. You'll love it!!!