I have been trying to get use to this site, but I have found others that I like much better. Although it is not exactly one stop shopping I can get most everything from three other web sites. My favorites:
http://www.trainorders.com
By far the best internet train site on the web. I hang out here and visit me in the chat room in the evening as we throw slide shows. They have webcams and lots of railroaders answering questions.
http://railroadnews.net
A great news site. Rob Carlson updates the news daily so this site contains a wealth of fresh railroad news.
http://www.railserve.com
If you are trying to find a web site then this is the best place to find it. Their system is extremely organized and finding anything is easy using this well thoughtout system of categories.