Well-known North American author (4)
I believe the answer is:
name
'well-known' is the definition.
(as in name brands)
'north american author' is the wordplay.
'north american' becomes 'na'.
'author' becomes 'me' (the author of the crossword).
'na'+'me'='NAME'
(Other definitions for name that I've seen before include "Mean sort of appellation" , "Title, term" , "Amen (anag)" , "celebrity" , "By which one is known" .)