If you live in Elgin, I might recommend heading North to Algonquin Dam or South to St. Charles dam.
You'll want to read this guy's site:
I don't think he usually says where his spots are, though.
I'm not giving away my super secret spots, but well-known ones which produce are:
Above the dam on Kimball St., East side of the river. There's fish below, but also a lot of snags, I usually avoid it.
Underneath the National St. Bridge, however you can get at it.
The stretch of Poplar Creek on Raymond St., where the bike path goes through.
South end of Walton Island for Carp and Drum, maybe some cats. Bottom rigs off the south end of the island, or in the deep channel on the east side. I almost never catch bass off Walton Island.
South end park in Dundee.
Bode lakes over in (Streamwood?). I've caught channel cats, yellow bass, smallies, etc. Seen some people catch small pike. There are MONSTERS there though. You see them at dusk, nobody ever seems to catch them. The signs for ice fishing claim there's Walleye in there too. I've never had a spot with so much promise produce so little, ha ha. Maybe you'll figure it out and let us know.
If you're a late night catfishing kinda guy, the place everyone goes for that is Trout Park. Mainly because of the parking lot by the river. Every night it's not too cold or rainy, there's people hanging out there with a few rods in the water.