This happened to me too, I was out of fandom for many years. But when I came back I started looking for a couple of fics I really wanted to read. I recall one was a massive fic set in period times dealing with dom/sub relationship between the two main characters. I searched high and low only to find that author had removed it from the internet.

Luckily some fics I was able to locate on still existing archives, and others I found on A03. It didn't help that my laptop was stolen a couple years ago so I lost ALL my bookmarks I'd spent years accumulating.

Have you tried the waybackmachine? I admit, it's been so long since I've used that I don't remember how it works, but I know sometimes you can find archived copies of things on that.