I love using CCMail. I first found it on Hotscripts.com, and it had an overwhelmingly positive response from past users (almost all gave it 5/5 - 60 people rated it at the time).
Setup takes about 2 minutes. It's the easiest thing in the world, and it doesn't require a database to run. The only caution I have is that it is written to output HTML4.01 transitional markup. I never tried validating it, so if this is something you feel strongly about, you will find yourself making modifications. However, I took a half hour, tore it apart one afternoon and make it XHTML1.1 compliant. If you're interested, I'd be happy to send you the file.
That's the one. I got your PM, and yes, I'd be happy to share my copy of the include.php file with you. Just let me know when you'd like me to send it. It might have a couple other adjustments to it, to the text in it, so take it for a test drive and make sure everything's suitable for you. The file is pretty easy to manipulate.