Writer's block getting worse? Initially, yes (9)
I believe the answer is:
hemingway
'writer's' is the definition.
(Hemingway is an example)
'block getting worse? initially yes' is the wordplay.
'block' becomes 'hemin' (I can't explain this - if you can you should give a lot more credence to this answer).
'initially' says to take the initial letters.
'yes' becomes 'ay'.
The initial letters of 'getting worse' is 'gw'.
'hemin'+'gw'+'ay'='HEMINGWAY'
Can you help me to learn more?
(Other definitions for hemingway that I've seen before include "Author of The Old Man and the Sea" , "He wrote Farewell to Arms" , "Ernest --, US author" , "Ernest . . . . . . . . . wrote 'For Whom the Bell Tolls'" , "See 5" .)