Do I need a comma after 'Tonight'? I know I can omit the word 'Tonight' but was curious about the punctuation.
Tonight 3 March 2013 at 7:50 pm, I received a call to investigate a $500 cash shortage ...
Yes. If you omit "Tonight", you should replace it with "On", which (obviously) would not require a comma after it.
I'm not a teacher of English, but I have spoken it for (almost) all of my life....