gistfile1.js

var label = Ti.UI.createLabel({
    text: 'Name',
    top: 8
});
label.height // return 0 when no width and height setting

var label = Ti.UI.createLabel({
    text: 'Blah,Blah,Blah,...',
    top: 8,
    width: 280,
    height: 'auto'
});

label.height
// the height will be changeg base on how long the text is 
// so you can get the top of next element by the label.height