number and letter generator

[shopwithdan.com]

Hi,
I have to short snippets that create lists of 3 # combos/3 letter combos,
I want to allow users to pick if the combos should be followed by .com, .net, etc. I tried to do it myself but the result is always ".com543"
http://droplister.com/tools/3char.html

Can someone help me add a schalar or something that can be defined like $tld=$_POST["tld"];
Can you help?

Random #s

<?
/*
1 - 999
*/
$ini = 0;
$fin = 999;
for($i=$ini; $i<=$fin; $i++)
{
printf( "%s<br />\r\n", str_pad($i, 3, "0", STR_PAD_LEFT) );
}
?>

Random letters

<?

$letra = array();
for($i=97; $i<=122; $i++)
{
$letra[] = chr($i);
}

foreach($letra AS $a) {
foreach($letra AS $b) {
foreach($letra AS $c) {
echo "$a$b$c<br />\r\n";

}
}
}
?>