how do i send an email through joomla

I have a system so folks can register for a class through my Joomla site (I believe it's 3.0). But from there, I would like to send folks an email filling variables from the registration. So something like:

Dear (name), thank you for registering for (class). 
This is to remind you your class is tomorrow, (date), at (place).

I believe for the registration, the system uses authorize.net

How can I accomplish this?

Thanks for the help!!

Solution

You can use JFactory:getMailer like suggested in the following post. I'm copying here his code example (modified it a bit):

$subject = "Here is the subject of your message.";
$body = "Here is the body of your message.";
$user = JFactory::getUser();
$to = $user->email;
$from = array("me@mydomain.com", "Brian Edgerton");

# Invoke JMail Class
$mailer = JFactory::getMailer();

# Set sender array so that my name will show up neatly in your inbox
$mailer->setSender($from);

# Add a recipient -- this can be a single address (string) or an array of addresses
$mailer->addRecipient($to);

$mailer->setSubject($subject);
$mailer->setBody($body);

# If you would like to send as HTML, include this line; otherwise, leave it out
$mailer->isHTML();

# Send once you have set all of your options
$mailer->send();

That's all there is to it for sending a simple email. If you would like to add carbon copy recipients, include the following before sending the email:

# Add a blind carbon copy
$mailer->addBCC("blindcopy@yourdomain.com");

Another alternative is using JMail::sendMail: http://docs.joomla.org/API17:JMail::sendMail