Exemplo de envio de um email com PHP

<?php

    
  $userid   = $_POST[newid];
  $password = substr(md5(time()),0,6);
  $email    = $_POST[newemail];



              
  // Email the new password to the person.
  $message = "Hello

Your personal account for the Project Web Site
has been created! 

Your personal login ID and password are as
follows:

    userid: $_POST[newid]
    password: $password

- Figo
";

  mail($_POST['newemail'],"Your Password for the Website",
       $message, "From:Figo <figo@blabla.com>");
         

?>

Para ver uma aplicação do código, vá a aqui.