Jquery Geocoding Script
Just a few things in no particular order:


Don't use long as a variable name. It's a reserved word in Javascript and can cause confusion.
If you're going to disable the country input in your form, you should probably just put the US keyword straight in your code. That is if you don't intend on enabling it.
You set ctryiso = $("#ctry").val() and then test ctryiso !== ''. Since you hard coded the country value in, that will always be true. Therefore, unnecessary test.
You don't need to initialize your lastQuery and lastResult to null. Any falsy value will do just fine in JS, including undefined.
If you look at the jQuery source code you'll see that the .click() simply calls another method and passes the values on. You can save a few function calls if you just call that other method directly.


Like so:

$('#search').click(function (e) {
    //Do stuff
}

//Do this one instead
$('#search').on('click', function (e) {
    //Do stuff
}


The 'click' can be replaced with any event of you're choosing. This gives you enormous power and control when setting up custom events.