You can subscribe to this blog and be notified every time I update it. I'll update mainly on Monday or Tuesday when I upload Sunday's sermon. Subscribe by left-clicking on the orange button or the "Subscribe" link in the right column. This will take you to a Feedburner page where you can select which service to subscribe through. I recommend Google Reader; it's what I use, and it's very easy. Very soon, you should be able to add this feed in iTunes. iTunes will take care of the rest of it and download this sermon for you every week. Or, you can just download it yourself from this website!
Let me know if you have any questions.