Oh My God!!
funnily enough: used for saying that you think something is surprising or unusual
you don’t say: used for saying that you are surprised by what someone has told you
heavens above: used for showing that you are very surprised
Well, I never (did): used for saying that you are very surprised
is that a fact?: used for answering someone when they have told you something that you consider surprising or unlikely to happen
you would not believe: used when you are going to tell someone about something unusual or surprising
of all things/people/places: used for expressing surprise that a particular thing/person/place is the one involved in something
now I’ve seen everything/it all: used for saying that you find something very shocking or surprising