Here is an icon I created for Doom

Copy DOOM.ICO into your doom directory (i.e. C:\DOOM)
Run Windows
Click ONCE on your current Doom icon in Program Manager
Press ALT-ENTER (or Select [F]ile, [P]roperties)
Clck on Change Icon (or Press ALT-I)
At File Name, type in C:\DOOM\DOOM.ICO (if C:\DOOM is your doom directory)
                     ^^^^^^^------------------replace with your directory name---
Click on OK twice.

The icon should appear.

Enjoy!

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