If you've got the time you should check out the Museum of Science and Industry. They have the layout that inspired most of the model railroaders around Chicago. They also have many pieces of railroad history like 999, the Pioneer Zephyr and many streetcars. Yes, I know it's an HO layout but it used to be O. About 25 years from now we'll get our turn.
Got to second a Chicago style dog (there are many nearly equal hot dog stands - usually the funnier the name, the better) or Chicago style pizza (Uno's is also good) to go with the LHS tour, museums, and railfanning. But, make a plan! Chitown is big, big, big.
Compared to other cities Chicago is very dense and compact. Compared to Atlanta area my closest shop is 35 round trip, the best shop is 150 round trip. Those same distances in Chicago get you to about 10 different hobby shops and a couple of train museums.
Personally. I'd skip the Wheaton show. It's 90% HO and Lionel stuff, and it's pretty weak in the summer months. I'd hit Rochelle, and Lombard Hobbies (it's on the way - sort of). And Des Plaines, Kato and Union, on another day.
It use to be O scale? I seen it a few times and I think it was HO and that had to be in the late 70s. Either that or my memory fades me lol!
B&G in Elgin is great. Friendly service. Grayland has a lot they also are a usual vendor at the Dupage show so if you want to him them there.. Thats alright too. Americas Best in Itasca is alright but you can do just as well at B&G and Grayland. Lombard hobbies is good. Walt's in Crest Hill is alright but probably not worth the trip if you are in the northern half of the burbs. That should pretty much take care of it.
