The Lake County Forest Preserve maintains several lakes with decent panfish and bass fishing throughout Lake County. I had a lot of luck at the Independence Grove facility in Libertyville that opened last year. Even caught a few Walleye and have heard of others taking Pike out of the 115 acre lake. I also have tried the Desplaines river but with little luck.
The Fox Chain of Lakes has lots of fish, and lots of fishermen. Links to the forest preserve and the Fox chain are on this site.
There a lot of different lakes and ponds out there to fish in the area, although most people might disagree, we are blessed with the area we get to fish. There are so many subdivisions and forest perserves that stock their ponds and lakes to be fished, any place in particular or species? Hopefully there is some close to you, I mean just either look on a map and check out the little ponds, or just drive around, I occasionly go "pond/lake Hunting" alot and most of the time am very successful. Good Luck and Tight Lines!
Although I don't flyfish, Papoose (Palos Hills) has had panfish popping the surface the last two days. It is a very weedy lake, and fly-fishers can place their presentation amoung weed pockets and do pretty good on panfish, and bass(when the water gets warmer). That's what I hear anyway!
OZ, who has had fish attack his float there, but not his bait ;0(