Steve Thomason's Industrial Narrow Gauge Site (link below) is about the best I've found. He has undertaken to catalog every industrial ng line still operating in the British Isles and has extensive information regarding ng lines on the European continent as well. He also sells a line of well-made videos to support the project. I've corresponded with Steve a few times, sent him som pics of American operations to include in his project. A very nice guy, and a good informative web site and videos. I recommend it highly.
J