I live in Pepin on the Wisconsin side...but haven't been able to fish the lake near as much as I would have liked so far.
I recommend that you get one of these lake maps from Fishing Hot Spots...
This is a great thing to start off with. There have been maps made by Sportsmens Connection and LakeMaster in the past....but I don't see them available on either of the websites at the moment.
I haven't heard of anyone fishing the lake itself for catfish...most folks fish the dams, or say the Chippewa River...or backwater areas with deep holes like down by La Crosse.