Where to find information, if at turning between valleys? (4,5)

I believe the answer is:

data files

'where to find information' is the definition.
(data is information)

'if at turning between valleys?' is the wordplay.
'turning' says the letters should be written in reverse.
'between' is an insertion indicator.
'valleys?' becomes 'dales' (dale is a kind of valley).
'if'+'at'='ifat'
'ifat' backwards is 'tafi'.
'tafi' going inside 'dales' is 'DATA FILES'.

I've seen this clue in The Guardian.

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