Page about wonderful building? (6)
I believe the answer is:
prefab
'building?' is the definition.
(I have seen 'Temporary building ' mean 'prefab' so perhaps 'building' could also mean 'prefab')
'page about wonderful' is the wordplay.
'page' becomes 'p'.
'about' becomes 're' ('re' means regarding or about).
'wonderful' becomes 'fab' (slang abbreviation of fabulous).
'p'+'re'+'fab'='PREFAB'
(Other definitions for prefab that I've seen before include "Type of house" , "Sort of building" , "Cheap building" , "Building assembled with sections made elsewhere" , "British inter-war temporary housing, popularly called" .)