BarII said:
I see commas, not dashes.
You'll want to keep in mind, Bar, that the examples you're looking at also include the "said" dialog tag. If you separate your dialog from your narrative with commas, you need some equivalent of said.
"Excuse me," he said as he flung his badge onto the counter, "I'm here to see Richard."
It's improper to use commas to set off the dialog without a dialog tag. As Maryn showed above, it's better to use periods.
"Excuse me." He flung his badge onto the counter. "I'm here to see Richard."
As for interrupting dialog with em-dashes, here's my philosophy: It depends on whether you're actually interrupting.
You're probably familiar with interrupting dialog at the end:
"Don't you dare walk away from—"
He spun around and threw a punch straight at my face.
Something physically interrupted the utterance of the dialog, so em-dash.
We can do that in the middle of a sentence, too:
"I'm just not that excited—" the carriage jarred over railroad tracks "—about seeing Aunt Virginia again."
The character is talking and that speech is interrupted by something. She stops talking when they hit the bump and then resumes after they've passed over it.
But sometimes you'll have simultaneous action/dialog, where you want to show what someone's doing while they're talking:
"This"—he waved a hand toward Dan dancing with the ghosts on the veranda—"is going to be a problem."
You could also say (and it's more common to do so):
He waved a hand toward Dan dancing with ghosts on the veranda. "This is going to be a problem."
Or
"This." He waved a hand toward Dan dancing with the ghosts on the veranda. "Is going to be a problem."
But some people are a bit put off by this construction because "This" and "Is going to be a problem" are fragments, even though we use fragments in dialog all the time.
But if you need to use em-dashes to place non-dialog (for example, you could also use thoughts in a first-person narrative ["This"—
Dear Lord, not again—"is going to be a problem."]) in the middle of dialog and you don't want to interrupt the flow with periods or dialog tags, the em-dashes go outside the quotation marks.
For your beta MS, I would offer the writer any of the following alternatives:
"Excuse me." I pulled on the officer's hat. "Where did you find him?"
I pulled on the officer's hat. "Excuse me. Where did you find him?"
"Excuse me"—I pulled on the officer's hat—"where did you find him?"
df "excuse me he said as"
