Bowie song covers for example - it's starting! (4,4)
I believe the answer is:
here goes
'it's starting' is the definition.
(phrase said as something begins)
'bowie song covers for example' is the wordplay.
'bowie song' becomes 'Heroes' (song by David Bowie).
'covers' indicates putting letters inside.
'for example' becomes 'eg' (short for 'exempli gratia', 'for example' in Latin).
'heroes' enclosing 'eg' is 'HERE GOES!'.
(Other definitions for here goes that I've seen before include "Words spoken before start of rash action?" , "Gee horse (anag.)" , "I'm starting" , "I'm about to start" , "I'm about to begin - ready, steady . . . . . . . ." .)