Possible Clues:

• Poet whose works include The Marriage of Heaven and Hell
• Artist in Blackpool?
• William ---, poet
• 'Eternity' writer William
• Griffin of the NBA
• Visionary born by stretch of water
• See 20 Across
• Poet, painter and illustrator left to cook hogs
• 2007 'American Idol' runner-up ___ Lewis
• Poet who wrote 'Tyger! Tyger! burning bright'