what sort of shows has he hosted?
He was host of the public radio comedy/music program "Le Show".
Introduction
Since 1983, Shearer has been the host of the public radio comedy/music program "Le Show", incorporating satire, music, and sketch comedy. He has written three books.

who provides the voice of mr smithers on the simpsons Harry Shearer where was he born? Los Angeles what else were his professions other than being a voice artist? He is also an actor, comedian, writer, musician, radio host, director and producer. to which radio network was he a host? National Public Radio
Radio comedy/music program. The public radio comedy/music program "Le Show". "Le Show"
Harry Shearer Harry Shearer Harry Shearer
"Le Show" and radio work "Le Show" and radio work "Le Show" and radio work
Since 1983, Shearer has been the host of the public radio comedy/music program "Le Show".  Since 1983, Shearer has been the host of the public radio comedy/music program "Le Show".  Since 1983, Shearer has been the host of the public radio comedy/music program "Le Show". 
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Harry Shearer [SEP] Introduction
In 1989, he joined the cast of the animated sitcom "The Simpsons"; he provides voices for characters including Mr. Burns, Waylon Smithers, Principal Skinner, Ned Flanders, Reverend Lovejoy, Kent Brockman, Dr. Hibbert and more. Shearer has appeared in films including "The Truman Show" (1998) and "A Mighty Wind" (2003), and has directed two, "Teddy Bears' Picnic" (2002) and "The Big Uneasy" (2010). Since 1983, Shearer has been the host of the public radio comedy/music program "Le Show", incorporating satire, music, and sketch comedy. He has written three books. Shearer has won a Primetime Emmy Award and has received several other Emmy and Grammy Award nominations.