you were close, a few mods like this should do it:

Code:

<script type="text/javascript">
function tomorrow(){
var dateFuture1 = new Date(2014,07,12,10,01,00),
dateNow = new Date();
dateFuture1.setDate(dateNow.getDate()+1);//sets day of month
dateFuture1.setFullYear(dateNow.getFullYear());//Sets year (four digits)
dateFuture1.setMonth(dateNow.getMonth());//sets month (from 0-11)
return dateFuture1;
}
function GetCount(ddate,iid){
var amount = ddate-new Date(); //calc milliseconds between dates
// if time is already past
if(amount < 0){
ddate= tomorrow();
iid.innerHTML="NOW";
}
// else date is still good
else{
days=0;hours=0;mins=0;secs=0;out="";
amount = Math.floor(amount/1000);//kill the "milliseconds" so just secs
days=Math.floor(amount/86400);//days
amount=amount%86400;
hours=Math.floor(amount/3600);//hours
amount=amount%3600;
mins=Math.floor(amount/60);//minutes
amount=amount%60;
secs=Math.floor(amount);//seconds
if(days != 0){out += days +" "+((days==1)?"day":"days")+", ";}
if(hours != 0){out += hours +" "+((hours==1)?"hour":"hours")+", ";}
out += mins +" "+((mins==1)?"min":"mins")+", ";
out += secs +" "+((secs==1)?"sec":"secs")+", ";
out = out.substr(0,out.length-2);
iid.innerHTML=out;
}
setTimeout(function(){GetCount(ddate,iid)}, 1000);
}
window.onload=function(){
GetCount(tomorrow(), document.getElementById('countbox') );
};
</script>
<span id="countbox"></span>

basically, more the tomorrow finder to a re-callable function, and move the setTimeout out of the *if *statement.

i also moved the id to element conversion to call-time, so you only have to use that relatively expensive DOM method once, not every second...