You might try the local chamber of commerce, I know that some years back you could get a map of Houghton Lake from the chamber there. It had depths, weed beds, public access and water access restuarants/pubs. I've got to think that if you called Gaylord Chamber of Commerce they could point you in the right direction.
Good Luck
[This message has been edited by Lance (edited 05-02-2000).]