Right next to the south entrance into Devils Lake State park is a small stream that holds brook trout.
Turn right as you exit the park on S. Lake Rd, go past County Road DL and you will see the stream in a couple hundred yards or so. It’s not a very big stream at all but I’ve been told repeatedly there are brook trout in there and I have seen people fishing it.
There is also a hiking trail that goes thru a marsh right next to that area as well. Don’t remember the name of it off the top of my head but if you get to Merry Mac’s camp ground, you’ve gone to far.
Black Earth creek is another good choice. A bit further away but it’s a much bigger and better trout stream.
Google “Black Earth Creek, Dane, Wisconsin”.
For the record, although I have gone trout fishing when I was younger, I certainly would not call myself a trout fisherman. I did however, grow up in this area and know it pretty well.