After taking a closer at the scenarios I have, they seem to be most of the scenarios that were once available at the old CivCity Forums. I looked at some pages on Internet Archive that had the CivCity Rome Forums Index of Data Content. Sadly, Internet Archive didn't archive the zip files.
Here is the downloads data content:
And the Internet Archive link: https://web.archive.org/web/20091006131403/http://www.civcityforums.com/data/content/
I unfortunately cannot remember where I downloaded them from, but I do know that I downloaded all that there were.