Try this variation ...
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Untitled</title>
<script type="text/javascript">
// Format of StoreDetails()
// Name,Addr1,Addr2,Addr3,Phone,FAX,Email,Webpage
var StoreDetails = [
['Please select an option','','','','','','','',''],
['Store 1','Name 1','Addr 1','Addr 1','Addr 1','Phone 1','FAX 1','Email 1','Webpage 1'],
['Store 2','Name 2','Addr 2','Addr 2','Addr 2','Phone 2','FAX 2','Email 2','Webpage 2'],
['Store 3','Name 3','Addr 3','Addr 3','Addr 3','Phone 3','FAX 3','Email 3','Webpage 3'],
['Store 4','Name 4','Addr 4','Addr 4','Addr 4','Phone 4','FAX 4','Email 4','Webpage 4'],
['Store 5','Name 5','Addr 5','Addr 5','Addr 5','Phone 5','FAX 5','Email 5','Webpage 5'] // Note: no comma
];
function Setup(TA) {
var str = "<select id='Store' onchange='StoreInfo()'>";
for (var i=0; i<StoreDetails.length; i++) {
str += '<option value="'+StoreDetails[i].join('|')+'">'+StoreDetails[i][0]+'</option>';
}
str +='</select>';
document.write(str);
}
function StoreInfo() {
var sel = document.getElementById('Store').selectedIndex;
var tmp = []; tmp.push(sel);
for (var i=1; i<9; i++) { tmp.push(StoreDetails[sel][i]); }
document.getElementById('txtName').value = tmp[1];
document.getElementById('txtAddr1').value = tmp[2];
document.getElementById('txtAddr2').value = tmp[3];
document.getElementById('txtAddr3').value = tmp[4];
document.getElementById('txtPhone').value = tmp[5];
document.getElementById('txtFAX').value = tmp[6];
document.getElementById('txtEmail').value = tmp[7];
document.getElementById('txtWebpage').value = tmp[8];
}
</script>
</head>
<body>
<form name="theform" onsubmit="CheckForm()">
<script type="text/javascript">Setup();</script>
<table border="0">
<tr><td>Name:</td><td><input type="text" id="txtName" size="30" value=""></td></tr>
<tr><td>Address 1:</td><td><input type="text" id="txtAddr1" size="30" value=""></td></tr>
<tr><td>Address 2:</td><td><input type="text" id="txtAddr2" size="30" value=""></td></tr>
<tr><td>Address 3:</td><td><input type="text" id="txtAddr3" size="30" value=""></td></tr>
<tr><td>Phone:</td><td><input type="text" id="txtPhone" size="30" value=""></td></tr>
<tr><td>FAX:</td><td><input type="text" id="txtFAX" size="30" value=""></td></tr>
<tr><td>Email:</td><td><input type="text" id="txtEmail" size="30" value=""></td></tr>
<tr><td>Webpage:</td><td><input type="text" id="txtWebpage" size="30" value=""></td></tr>
</table>
</form>
</body>
</html>