I don’t think there is much online for a decent map..I would head to a local Gander, Dicks, Sportsmans Warehouse, or Thorne bros.. and pick up the Tutts map…that is the best one on the market..not too spendy either..if you plan on fishing Mille Lacs often not a bad tool to have along…
I think Lake Master has this lake broken down to 4 different areas that have great detail of a few favortie reefs/flats. I have 2 of them and they have waypoints on them. I got mine at Gander