ID CS3: How to place a rotated text box against the side of a photo box?

Here you go. A fun exercise in finding out the right parameter for various things.

var photo = app.selection[0];
if (photo == undefined || photo.constructor.name != "Rectangle")
{
 alert ("Please select a picture");
} else
{
 var theText = prompt ("Text", "Photo Joe Klein", "Enter straddle line");
 if (theText != null)
 {
  var oldHorizontalUnits = app.activeDocument.viewPreferences.horizontalMeasurementUnits;
  var oldVerticalUnits = app.activeDocument.viewPreferences.verticalMeasurementUnits;
  app.activeDocument.viewPreferences.horizontalMeasurementUnits = MeasurementUnits.POINTS;
  app.activeDocument.viewPreferences.verticalMeasurementUnits = MeasurementUnits.POINTS;
  xpos = photo.geometricBounds[2];
  ypos = photo.geometricBounds[3];
  frame = app.activeDocument.textFrames.add (undefined, undefined, undefined, {absoluteRotationAngle:90} );
  frame.geometricBounds = [xpos+1,ypos, xpos-96, ypos+12];
  app.activeDocument.viewPreferences.horizontalMeasurementUnits = oldHorizontalUnits;
  app.activeDocument.viewPreferences.verticalMeasurementUnits = oldVerticalUnits;
  frame.parentStory.appliedFont = app.fonts.item("Helvetica\tMedium");
  frame.parentStory.appliedFontSize = 5;
  frame.parentStory.baselineShift = -6;
  frame.parentStory.tracking = -15;
  frame.parentStory.kerningMethod = "Optical";
  frame.parentStory.justification = Justification.LEFT_ALIGN;
  frame.contents = theText;
 }
}

Tested on CS; the rotation changed a bit with CS2 or CS3, so it might not work right out of the box (and you'll have to wait until Monday for me, or s/o else to fix it).

If your by-line is always the same, you could remove the 'prompt' statement and replace it with a simple assignment:

theText = "Photo Joe Klein";