You're Welcome! I know a little how to navigate around here, but not as much as the experts, but I try!
As you are seeing other countdowns in people's signature, you can just right click them and it will take you to the countdown website or look carefully and you will see that the website is listed and you can google it. Once on the ticker website of your choice, it will walk you through making a countdown. After you create one you will copy and paste it into your signature (under "user CP").
Edited to add: copy the "url" code to copy it into your signature.