I got it to work using the eval() function in javascript thanks to Randy Pearson on the wwthread. It looks like it may work in NS as well as IE.

<SCRIPT LANGUAGE="JavaScript">

var lctext = ' ';
function ckvar(lctext,i){
var lostrno=eval("userform.strno"+i)
var lostreet=eval("userform.street"+i)
var locity=eval("userform.city"+i)

switch (lctext){
   case "Memphis Police Department" : 
     lostrno.value='201'
     lostreet.value='Poplar';
     locity.value='Memphis';
     break;
   case "Shelby County Sheriff's Office" : 
     lostrno.value='201'
     lostreet.value='Poplar';
     locity.value='Memphis';
      break;
 etc, etc, etc.