The most common and most likely answer to this crossword clue is the 11 plus 4 letter word INFORMATION DESK
I've seen this crossword clue in The Guardian
I
N
F
O
R
M
A
T
I
O
N
D
E
S
K
Buddy explains!
The straight part
We know that "Where to obtain counter-intelligence" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case where to obtain counter-intelligence = information desk.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.