in reply to where i can find the source of HTML main page of the webmin ?
You'll probably have more specific help contacting specific Webmin forums (like the ones listed in the Community section of Webmin site - http://www.webmin.com/community.html).
The documentation (including tutorials) is also available through a wiki at the Documentations section of the same site (http://www.webmin.com/docs.html). And there is always Google to help you out of it.
Maybe these are good starting points to your questions
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