I've hunted with Grey Bruce Outfitters, near walkerton. We arrived the evening before and were up early. Stayed at his place, basement is nicely finished and clean. Hunted a few spots and ended up taking a jake in an amazing double with my buddy. All in all, good service and fun hunt. It was our first turkey hunt. They also had a guy up from the states who was here doing a grand slam tour or something, so they are familiar with taking out non residents.
Also in the same area is Wingfeathers. He used to work for Grey Bruce and they have a bit of a feud. Haven't hunted with them but have heard others here mention they are also good.
Good luck.