This electron app finds game covers for all your games in the new Steam library. It searches multiple sources, and creates its own cover using gm if it can't find one.
Before running the app, install GraphicsMagick if you want the app to create its own covers when it can't find one. HTTP://WWW.GRAPHICSMAGICK.ORG/
Download the App here:
http://www.mediafire.com/file/a4h28qo4c0zlbp9/SteamCoverFinder_Setup_1.0.0.exe/file OR https://drive.google.com/open?id=1383yMyes2UmB7x27HKPFWX2O-cwYRzmm
Run the Setup file. It may get firewalled but please allow it to run. It won't do anything to your PC. Promise :)