O Gauge Railroading Forum.
https://ogrforum.ogaugerr.com/
Although it is called " O Gauge" there are separate forums for all types of toy and model trains. Most of the activity is in the Lionel O Gauge section which covers both new and all types of vintage. There is a lot of good discussions about operating trains, repairing trains, restoration, layout building, and general collecting. Like Ford Barn, if you ask a question about anything Lionel related, you will get a dozen answers with various oppinions in a very short time!
I collect original, pre-war Lionel standard gauge. There is some activity on this website for standard gauge collectors as well.
What do you like?