WordPress 2.9 built with new ability to Extend User Contact Info, this tricks can be done by added some code on functions.php in your current theme. We can added many contact info, depend on your needed. To do extend user contact info, open the files and add this code
<?php
function my_new_contactmethods( $contactmethods ) {
// Add Twitter
$contactmethods['twitter'] = 'Twitter';
//add Facebook
$contactmethods['facebook'] = 'Facebook';
return $contactmethods;
}
add_filter('user_contactmethods','my_new_contactmethods',10,1);
?>
And the result of this tricks will be like this,
This is only basic usage, you can made it more complicated depend on your creative minds 
Nice tutorial, it doesn’t get much simpler than that now! The old script I used to do this was fairly short, but not as good as this, thanks!
Thanks you Michael…
All of your tutorials are great. Cheers for taking the time to post them
Very Nice!! This is what I’m looking for! Thanks!
Thanks for this. It’s a really simple way of adding new fields. Is there a way to also include a description span like “Usernames cannot be changed.”
Thanks in advance.