One of the biggies on the web is AJC Kids of Wichita, TX, their on-line presence includes a top notch website with very very good pricing and informative list of past/present/future listings of Marklin items in all gauges. If something is in stock it is usually featured with a ‘+’ sign in green below the item description, checkout is delayed for 24-48 hours, they get back to you when your order is prepared. Here you have the opportunity to fill out a collection with items that are not available elsewhere for good prices to boot! Guy the owner is an affable person who attends the Toy Fair in Germany, here you can order those limited and exclusive models only available at the fair. My Wife and I have been to the store in person and I can attest to the large inventory, rest assured you will get the item you order from the website if you see a green ‘+’ sign on the listing. Also check back often because sometimes things go on unannounced sales posted on the website, prices during these sales go from good to super good. Highly recommended. Guy posts lots of photos from the Toy Fair so check them out on his website, next best thing to being there in person.

http://ajckids.com