Note, Scombo is a work in progress but you can download it here:

It enables you to include selective combo boxes that only show data relevant to parent select boxes.

As we add more options and data we will post them here. Along with a full set of instructions and documentation.

Selected Region:$region Selected Country:$country Selected State/Province:$stateprovince Selected City:$city "; ?>
Select one of the options in the Select boxes
Tick this box to submit the text, unchecked will submit field values type=checkbox onclick="if(this.checked)returnTextValues=true; else returnTextValues=false;">
Geographic region:  Country:  County/State/Province:  City: