Particular person originally from American location (7)
I believe the answer is:
fusspot
'particular person' is the definition.
(person who is fussy or particular)
'originally from american location' is the wordplay.
'originally' indicates taking the first letters.
'american' becomes 'US' (United States).
'location' becomes 'spot' (spot is a kind of location).
The first letter of 'from' is 'f'.
'f'+'us'+'spot'='FUSSPOT'
(Other definitions for fusspot that I've seen before include "Over-fastidious person" , "song-and-dance man?" , "Hard-to-please person" , "I worry" , "one worrying about trifles" .)