Last fish fry I went to was in Trevor, WI -- just over the border, so not terribly far from the northerly suburbs. It is an old, traditional, family-owned supper club called the Colony House Restaurant. Pike, perch, blue gill, or cod. Cooked to order.

http://w.singlepage.com/colony-house-restaurant-3/menu

Another just over the border data point:
Milwaukee Grill
2601 Morse St, Janesville, WI 53545
www.milwaukeegrill.com

They have fresh lake perch, bluegill, and fish fry cod (the latter least expensive), very good fried chicken, and a cod/chicken combo, plus salads, burgers, sandwiches. Sue had chicken, I had perch which were crumb coated and pan fried. Choice of potato including pancake (me) and crinkle cut sweet potato fries (her). Slaw was nothing to write home about.

Service was very good, prices cheap except for the perch ($17.50 - not awful but out of cheap territory, versus $10 for two pieces of chicken).

Just off 90/39 and US14, worth a trip.