Good news: You don't need to manually add data to xml files to have an updated RSS. There are free tools that will crawl your site and create it for you. Some have understandable limitations (if your site has lots of info) but most of them are just fine. For more advanced stuff you can upgrade your account.
I don't know if I can mention the names of the sites on this area but just search "rss out of any site" and you'll find them.
There you go, good luck.