Notes describing sheep liver, perhaps, somewhere in US (3,7)
I believe the answer is:
new england
'in us' is the definition.
('New England' is part of 'us')
'notes describing sheep liver perhaps' is the wordplay.
'notes' becomes 'nn' (I've seen this in other clues).
'describing' means one lot of letters goes inside another (describe can mean to form the outline of).
'sheep' becomes 'ewe' (ewe is a kind of sheep).
'liver perhaps' becomes 'gland'.
'nn' enclosing 'ewe' is 'newen'.
'newen'+'gland'='NEW ENGLAND'
'somewhere' acts as a link.
I am not very happy about this link. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for new england that I've seen before include "Part of USA" , "More than one state" , "NE USA" , "on the eastern seaboard" , "Six states together making a region of the USA" .)