http://wordpress.org/plugins/search.php?q=better+notifications
I see this plugin gets good ratings and can do what you want (configure the email to come from some other email address): http://wordpress.org/plugins/wp-better-emails/
You can change this by overriding the function wp_new_user_notification(). This is what WordPress calls a “pluggable function,” meaning that before WordPress core defines the function, it checks to see whether you have defined your own.
So, in your functions.php file (or in a plugin file, if you’d like) you can create your own function:
function wp_new_user_notification($user_id, $plaintext_pass = '') {
//do stuff here.
}
You will want to copy exactly the wp_new_user_notification function found in wp-includes/pluggable.php file. The find the line that reads:
wp_mail($user->user_email, sprintf(__('[%s] Your username and password'), $blogname), $message);
and replace it with these lines:
$headers = 'From: Blog Name <username@example.com>' . "\r\n"; // fill this in with the e-mail address and from name that you want to use
wp_mail($user->user_email, sprintf(__('[%s] Your username and password'), $blogname), $message, $headers);
And that will cause the e-mails to come from the address you want.
Oh, and the plugin bemdesign shared while I was writing my response is a good option, too, if you don’t want to do any coding. 🙂
