Sekim i spent several days - if not weeks- to go through all the threads in the workshop section and find the final versions of fanspansions not mentioned in the homepage listing at the
fan made expansions pageAfter that it's a matter of checking back and keeping up to date best you can
(There's quite a few great ideas still waiting to be completed by the way.)
One of the moderators invented a search word to be able to quickly track down the final versions as soon as an update in the list mentioned before could be made. But after some period of time even that was banned. As my search was made almost a year ago i can not recall who it was or what is the search word was. For you I suppose you need to also check all threads of interest, work you way from last post to first in each thread to find the final versions as they are posted last mostly.
I would say whenever an update can be made, the mods should send an e-mail to all listed members asking for a hyperlink to their final versions fan made expansions, if any. That would be the quickest way to be able to complete the list. Well, if all respond that is.