Mental imagery of IT career? (9)
I believe the answer is:
evocation
'mental imagery' is the definition.
(evocation is a kind of mental imagery)
'it career?' is the wordplay.
'it' becomes 'e' ('e' can mean 'electronic' which is similar to 'IT').
'career?' becomes 'vocation' ('vocation' can be a synonym of 'career').
'e'+'vocation'='EVOCATION'
'of' is the link.
(Other definitions for evocation that I've seen before include "A calling forth" , "A spell" .)