Here are ColecoVision overlays that have been scanned into picture files.
Titles in red are missing. Please email if you can contribute.

How to Save & Print an Overlay.
 

 
Official Overlays:

Homebrew Overlays::
Here are some homemade overlays for games that could have used them.
And some alternates for ones that could have been better.
Want to get creative and show off your efforts? Here's a couple Blank overlays to help get you started.