In plain-old JavaScript you can do this:
var inputs = document.getElementsByTagName('input');
for(var i = 0; i < inputs.length; i++) {
if(inputs[i].type.toLowerCase() == 'text') {
alert(inputs[i].value);
}
}
In jQuery, you would just do:
// select all inputs of type 'text' on the page
$("input:text")
// hide all text inputs which are descendants of div class="foo"
$("div.foo input:text").hide();