input

var node_list = document.getElementsByTagName('input');

for (var i = 0; i < node_list.length; i++) {
    var node = node_list[i];

    if (node.getAttribute('type') == 'text') {
        // do something here with a <input type="text" .../>
        // we alert its value here
        alert(node.value);
    }
}