Heroes VII

You would be better off looking for photos of helmets, rather than drawings.

Unfortunately, feathers don't last that long. Here, for example, is a helmet:

http://www.pictureshack.ru/images/5305015.jpg

In the middle, there was a crest made of horsehair, and on either side of it, you can see two holes for feathers.

Another example of an elaborate helmet: Thracian, bronze, 4th century BC:

http://www.pictureshack.ru/images/6581helmet12.jpg