Recently I have been working on a custom checkout page for one of our clients in Sweden. I had some trouble figuring out how to send default Magento order email with all of the order info. After an hour or so of studying Magento core code, here is the solution on how to send email after successful order has been made.
Not sure how useful this alone will be for you, so I’ll throw a little advice along the way. When trying to figure how to reuse Magento code, separate some time to study the Model classes with more detail. Then “tapping into” and reusing some of them should be far more easier.