Walleye are by far my favorite fish.
And yes- they are caught year round including through the ice.
Michigan, Minnesota and Wisconsin have some amazing inland lakes to catch walleye without having to hit the bigger(great lakes), which can be tough at times.
Fly in fishing in Canada is one of the best ways to catch cold, fresh walleye. Cooked by light breading, a touch of salt and pepper at shore lunch- is amazing! Throw in the fried potatoes and a few onions, some baked beans- and some of the best meals I have ever enjoyed.