NW Indiana here too...non-boater...here's my pics for best places to fish in this neck of the woods: Wolf Lake in Hammond for musky, pike, walleye and large & smallmouth bass; Lake George in Hobart for bass and slab crappies; Long Lake in Valparaiso for bass n gills; Flint Lake in Valparaiso for bass, crappies and walleyes; Willow Slough near Morocco (sp) for bass and gills; Pine/Stone Lake in LaPorte for bass, crappies and giant sunfish; Salt Creek, Beauty Creek, and Trail Creek for trout and salmon; Kankakee River for walleye, large & smallmouth bass, crappies and pike; Tippiecanoe River for smallmouth, walleye and pike; and a ton of small bodies of water near Hammond area in industrial and/or shopping areas that are loaded with slab crappies and big bass.
Well, that ought to be enough to get you started anyway...my favorite is the Kankakee River - plenty of public access from the state line to an area near South Bend where the river starts/is joined by the Kankakee Ditch...ooops and don't forget the Yellow River for excellent smallmouth fishing too.
Do you know if you can still rent boats on Wahoub? My Dad use to take us there when we were kids and the public was able to rent boats no public launch though.