Interactive select menus

Hi, I'm trying to make interactive select menus where the user selects an item from a drop down menu and it creates a new dropdown menu dynamically under it.

I don't want it done with innerHTML, so it involves a good deal on nodes and such. And I'm having trouble right at the part where I need to create the 2nd select box with values and the text in them.

My test code so far involves selecting a car to purchase. First option would be type of car, and then the second would be price range.

Here's my code so far:
<!--
var choiceOne;
var choiceTwo;
var choiceThree;

//first selection to determine dropdown menus
function firstChoice (selection){
//user does not select
if (selection == 1) {
alert('Please select the type of car to get started!');
}

//user selects "sedan"
else if (selection == 2) {
choiceOne = "sedan";
choiceSedan2();
}

//user selects "SUV"
else if (selection == 3) {
choiceOne = "SUV";
}
}

//if user selects "sedan" as the first choice
function choiceSedan2() {
//creates the select element along with its attributes
selectElement=document.createElement('select');
selectElement.setAttribute("name", "dropdown2");
selectElement.setAttribute("id", "dropdown2id");
selectElement.setAttribute("onchange", "alert('it works')");

//creates each option in the select menu
optionElement=document.createElement('option');
optionElement.setAttribute("value", "1");
optionElement.setAttribute("label", "Please select your price range"); //here's the trouble spot - what would I have to do to display the text in the select box?

selectElement.appendChild(optionElement);
document.getElementById('dropSecond').appendChild( selectElement);
}

//-->
</script>


Here's the HTML:

<form name="shopper" method="POST" action=""><h2>

<!-- first dropdown -->
<div id="dropFirst">
<select id="dropdown1id" name="dropdown1" onchange="firstChoice(this.options[this.selectedIndex].value)">
<option value="1" selected>Please select the type of vehicle</option>
<option value="2">Sedan</option>
<option value="3">SUV</option>
</select>
</div>

<!-- 2nd dropdown location -->
<div id="dropSecond">

</div>


The 2nd dropdown would be created in the dropSecond div. Please help!! Thank you.