Was in Chicago today and visited three hobby shops, all on the NE side out toward O'Hare.
The best of the 3 was Grayland Station. I had heard great things, and Steve the owner didn't disappoint. What an awesome, packed, amazing find. He has some very hard to find items including I would estimate over 200 new Exactrail releases at good prices. I was looking for a HO Railbox Early Combo Door, but settled for a single door. I picked up two more Exactrail pieces: a 50ft Southern waffle box car and a 4780 Garvey Grain green covered 3 bay hopper. He is normally closed on Tuesdays (we lucked out and he came around the corner and let us in, my buddy is a regular), so the owner is extremely nice. Lots of Walthers, Atlas, Kato, Intermountain, Athearn RTR & Genesis. If you are into model airplanes (non-RC), particularly airliners, this is your shop. Amazing trains though too. Mostly HO, but a good bit of N. It is a bit disorganized but just a tremendous amount of finds here. Way cool. Website is just about the shop, but he will be glad to work with you if you call up, free shipping over $100 order and great deal on IM wheelsets.
http://www.graylandstation.com/
A close second was the very nice shop at Des Plaines, in well, Des Plaines, again NE of Chicago and not far from Grayland. It is 4 times the size of Grayland, and specializes in all gauges of trains. Very organized store. Excellent staff, very helpful, and an excellent selection. Prices are big city, but the people who work there are very approachable and helpful so worth it. Bought a few hobby staples/must haves on the workbench, but didnt burn a hole in my pocket.
http://www.desplaineshobbies.com/store/
Went also to Chicagoland Hobbies NE of Chicago. Nice shop, most things at retail and while nice, it was a bit of a letdown after the other two.
http://chicagolandtoysandhobbies.com/
It was a fun day.
Brad