I don't know about you lads, but trying to find 3rd party add-ons sites is like digging into a never ending black hole of nothing I know of Just Trains I know of Chris Trains I know of Train Sim Mods But where on earth are the rest?
Switch Point Simulations, Searchlight Simulations, Diesel Workshop, Armstrong Powerhouse, Railworks America, and of course the Steam store/workshop.
Here is my website. All items typically have links to where to find the product https://sites.google.com/view/trainsimulatorcontent/home Enjoy
My bad - I was copy and pasting on another page with that link Try this https://forums.dovetailgames.com/threads/third-party-repository.3548/