passing value thru querystring

I have one textbox and dropdownlist.I want to pass the value of these fields in querystring before I store the value in a tbale. I would like to use java script for aquiring such that I need to concatenate value and pass this into a querystring using sql proc. I am a newbie in using javascript ..can anyone help me out
<script type="text/javascript">  var str1 = "Welcome";  var str2 = "To";  var str3 = "Javascript";  var result = str1 +" "+ str2 +" "+ str3;  document.write(result);