Garrison Keillor did “A Prairie Home Companion” for forty years, wrote fiction and comedy, invented a town called Lake Wobegon where all the children are above average, even though he himself grew up evangelical in a small separatist flock where all the children expected the imminent end of the world. He’s busy in retirement, having written a memoir and a book of Limericks and is at work on a musical and a Lake Wobegon screenplay, and he continues to do the “Writers Almanac” sent out daily to internet subscribers.