Searching for "xsd" (xml schema document), the actual specs only come up at the advanced level, which is pretty accurate if you've ever suffered through them. Wikipedia entries appear here too. http://www.google.com.au/search?tbs=rl%3A1%2Crls%3A2&q=x...

intermediate gives you tutes and tools.

basic has news, forums posts, youtube (comments?) and (apparently) random-ish lists

You can also use it to filter HN, for the advanced "interesting" comments: http://www.google.com.au/search?tbs=rl:1,rls:2&q=site:ne...