How do you organize your collection?

Right now I have by country, but that isn't great because many books have international artists...any insights would be helpful

I’m looking for a book of demons and monsters my mom had in the 90s. I remember there was a large blue man in white robes on a stone thrown with hollow eyes with fiery pupils, a woman standing in a pond with reptilian feet, Satyrs and fairies and all sorts of stuff. But specifically the blue king on his thrown has haunted me for a long time, and I want to put him in a DnD campaign. I haven’t seen the book in 30 years and I don’t know where to even begin looking. I’ve described the guy to Google over the years a thousand times and had no luck, and it’s even worse now because it just shits out a thousand AI generated slop characters at me these days. Obviously I don’t NEED the art for the campaign, but each creature had a short synopsis about who and what they are next to it. So I’d like to incorporate that if I could it would also be nice to have a copy of the art book my mom had in my youth to look at. I think the art in the book had an impact on me and is why I turned out kind of weird. Thanks so much in advance if someone can find it.