Help with decoding error messages?

Folks (and the esteemed Mr.Oskoboiny:
  I write copiously and regularly on HTML and XHTML for more low-
tech members of the Web community. One of the biggest challenges in
encouraging such people to use the validator is that they're almost
all inexperienced in reading parser- or compiler-style error messages,
and in using that information to figure out exactly what changes or
repairs should be made to their documents.
  Of course, HTML Tidy (and related toolkits) go a long way to helping
out with such things, but I'm wondering if anybody can point me to
resources on the following:
(a) a complete list of validator error messages
(b) guidelines on how to read and interpret the validator's output
I'm not expecting to find anything terribly user friendly (I figure I
can handle that part) but I have been unable to come up with any 
comprehensive or terribly detailed on this subject.
  Any suggestions, ideas, or pointers would be greatly appreciated.
TIA,
  --Ed--

Ed Tittel    2207 Klattenhoff Dr, Austin, TX  78728-5480
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