There are many good sources of information about Net etiquette,
including these articles, which are regularly posted to
news.announce.newusers and news.answers:

 * Emily Postnews Answers Your Questions on Netiquette
 * Hints on writing style for Usenet
 * How to find the right place to post (FAQ)
 * A Primer on How to Work With the Usenet Community
 * Rules for posting to Usenet

These and other news.announce.newusers articles are archived in all
the usual FAQ archives including:

http://www.cis.ohio-state.edu/hypertext/faq/bngusenet/news/announce/newusers/top.html

ftp://rtfm.mit.edu/pub/usenet-by-group/news.announce.newusers

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