My site Trainz Resourses Directory already lists 90% of Trainz sites and the remaining 10% will be up next week. Posting the sites on this forum isn't a really good idea because the thread will be buried in a few days. If you want to send me the list I'll go through it to see if I've missed any, but I doubt it. There are also several other places where sites are listed.
My email address can be easily found on the web site.