How to automatically add something to value $address?
echo '<input type="text" id="address" name="address" value="'.$address.'" />';

<form action="" method="get">
    <input  type="text" name="myAddress">
    <input type="text" name="city">
    <input type="text" name="county">
    <input type="submit" value="Go Search">
</form>