Is there any publication that provides suggested prices for used large-scale trains?
Kalmbach Publishing Co. publishes Greenberg’s Pocket Price Guides for various toy train lines. I know of no published information for LGB, Bachmann, USA Trains, Aristo-Craft, Hartland, or other manufacturers. Your best bet is to read the want ads in the magazines and on the Internet and send for people’s lists. You can also visit online auctions such as eBay and see what prices items have been selling for. Over time you should get a feel for what things are selling for.