Backwaters have been iced over and people fishing for weeks now. The main channel is mostly locked up after the cold weekend but still probably not safe. Tried spudding my way out of the bay at Dresbach this morning and didn't get out very far before I hit a spot with 2" on top, water in the middle, then another layer of ice underneath.
Coming from Beloit you could always head to Dubuque and then turn right and drive up the river road until you see people fishing and join them. If you've got an ATV or something that you wanna use then Lake Onalaska is probably your best bet.