There should be no need for a tutorial. All you need to do is look at an example document and then use PHP/Perl/Whatever to generate the example, substituting the example data for your own. Study the documentation to make sure you understand how the element is supposed to be used, and the same for the element (it must be a unique identifier, which can be a permanent URL). You should make sure your feed is not in a password-protected directory, but the content its items link to can be.
You can also hand code the feed if you wish, but that can be very time consuming if you are doing updates all the time. I used to do it that way before I switched to a dynamic website a few years ago.
-- si-blog --
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