ImageMaps are not available in New Sites because we don't have HTML editing capabilities. Google Drawings is a sort of a work-around.
I created a Google Drawing in Drive and made the text links.
I set the sharing to public and copied the link to it.
I used the embed URL function to insert it.
OR you can use the "From Drive" option and select the drawing.
Note that you can use text links or image links.
View the video on the left. It is a good tutorial about how to make Image Maps with Google Drawings.
Another good tutorial