Here's a double stop break for "Across the Alley From the Alamo." I use my middle and index fingers to play all of the double stops. If you play this tab in TablEdit, it doesn't sound right, because the eight notes aren't "swung." I'm not sure how to do that with TablEdit yet, so just remember to swing the notes when you play it.
http://www.banjohangout.org/tab/browse.asp?m=detail&v=22980
Here's the version by the Quebe Sisters that I based it from: