Possible Clues:

• 'Treasure Island' narrator
• 'Taxi' role
• ''Huckleberry Finn'' character
• Diamond -- Brady
• Name with Slim or Diamond
• Name that sounds like a place to work out
• Halpert of 'The Office'
• Belushi of 'The Defenders'
• Carrey or Henson
• Creator of Bert and Ernie