Food shop found by American composer (6)
I believe the answer is:
delius
'composer' is the definition.
(I know that Delius is a composer)
'food shop found by american' is the wordplay.
'food shop' becomes 'deli' (short for delicatessen).
'found by' means one lot of letters go next to another.
'american' becomes 'US' (abbreviation for United States).
'deli'+'us'='DELIUS'
(Other definitions for delius that I've seen before include "Frederick -, nature-inspired Eng. composer" , "The Walk to the Paradise Garden composer" , "Frederick -, composer of Sea Drift, Appalachia" , "English composer, Frederick (1862-1934)" , "Bradford-born composer" .)