I hear Hogzilla in Battle Creek (889 W. Colombia Ave), FooJays in Kalamazoo (1200 W. Patterson), and Hog Wild BBQ in Holland are pretty good. Also, West Texas BBQ in Jackson was rated the best BBQ in Michigan in 1012 by MLive. If you want a rreal treat and don't mind driving top Royal Oak, Lockharts is the best around, and Pitmaster BBQ Bubba (a member here) makes the best brisket north of Dallas...
When I lived in K'zoo we went to a little joint downtown that was excellent, but unfortunately closed in 2008. It was the only place in town we liked, so that's when I bought my Char Griller and learned to cook my own.