hi
i know it is not in champaign county but it is close. try walnut point state park. last week i took 3 catfish and 1 bass. cats were 2.5 to 3ibs. and the bass was 3.25. i live in champaign county and it is 20min away, thats where we aslo camp.
if you dont have a boat you can rent one. or they have a lot of docks to fish from.
good luck.