Tom and Anna agitated, in a state (7)
I believe the answer is:
montana
'state' is the definition.
(state of the US)
'tom and anna agitated' is the wordplay.
'and' says to put letters next to each other.
'agitated' indicates an anagram.
'tom' put after 'anna' is 'annatom'.
'annatom' is an anagram of 'MONTANA'.
'in a' acts as a link.
(Other definitions for montana that I've seen before include "Nato man (anag) - US state" , "One US state ..." , "The "Big Sky State"" , "Send manna to this US state" , "North-western state bordering Canada" .)