I'm from Midwestern Ontario and a few of my favorites have been mentioned. I do love the shop in Exeter, beautiful and full of projects. The Quilted Nine Patch is beautiful, with an awesome restaurant called the "CrossRoads" and mercantile shop attached. There's E & E Cloths and Creations in Newton, the middle of nowhere, recently expanded and she offers classes as well. Her prices are very reasonable, sometimes less than Len's.
I picked up 2 business cards from a Quilt Show held in Teeswater last year. They are clipped to my book in anticipation of a road trip that might take me in their direction. "Thread's That Bind" in Maxwell, Hwy #4, and "Mothers' Fabric" at the Spirit Rock Motel, Wiarton. I have yet to visit them.
"Quilters by the Square" in Goderich is another one I'd like to check out. Not sure if they were affected by that Tornado a couple of years ago or not.