I have a contour map that is provided to me by a private company. it comes in the form of a .dwg that works for autocad. In the past i have gotten contour data from usgs but the data provided to me is much more accurate. I want these contours in the .dwg to get loaded into arcmap so I can use them to delineate watersheds as per usual procedure.
Try to open .dwg file from ArcMap's add data option, locate the .dwg file, double click on it and it will show you it's sub-files, open Polyline file or any other file from it as u desire.
Then you can create its boundary and DEM to carry out your tasks.