Journalist is concerned about liquor (8)
I believe the answer is:
reporter
'journalist' is the definition.
(I've seen this before)
'concerned about liquor' is the wordplay.
'concerned about' becomes 're' (regarding).
'liquor' becomes 'porter' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
're'+'porter'='REPORTER'
'is' is the link.
Can you help me to learn more?
(Other definitions for reporter that I've seen before include "One who writes the news for the media" , "One may get a story" , "News writer" , "hacker?" , "Newspaper worker" .)