King and Harry -- we longed for information (9)
I believe the answer is:
knowledge
'for information' is the definition.
(I've seen this before)
'king and harry we longed' is the wordplay.
'king' becomes 'K' (abbreviation for king in chess).
'and' is a charade indicator (letters next to each other).
'harry' is an anagram indicator (harry can mean to attack or spoil).
'we'+'longed'='welonged'
'welonged' is an anagram of 'nowledge'.
'k'+'nowledge'='KNOWLEDGE'
(Other definitions for knowledge that I've seen before include "Info" , "a small amount is risky" , "Information - erudition" , "Result of learning - awareness" , "Cognition, wisdom" .)