Perfect Brewing in Libertyville. I've only been there once and wasn't too impressed but to be honest I didn't look around too much as I was only looking to pick up one item. I usually buy everything online.
Perfect Brewing is closed. Growmasters is the only one in that area. Brew and Grow in Crystal Lake is my preference but thats gonna be about 45 minutes from Mundelein. Anything else in the area is going to be Chicago or western suburbs