"Karl Warner" wrote in message
...

Are there any rules, conventions or etiquette for posting in a newsgroup?

Certainly.

Where might I find such?

Here are some links on the web:
http://www.newsreaders.com/guide/netiquette.html
http://www.fau.edu/netiquette/net/elec.html
http://www.use-net.ch/netiquette_engl.html

Further, you may be interested in this page:
http://www.cs.indiana.edu/docproject/zen/zen-1.0_6.html

For example, I am curious about posting at the top or
bottom of a reply.

One neither top-posts nor bottom-posts. Instead, the correct way to reply is
to trim the previous post to just the points you wish to address, and to
intersperse comments appropriately.

--
Warm Regards,

Claire Petersky
Personal page: http://www.geocities.com/cpetersky/
See the books I've set free at:
http://bookcrossing.com/referral/Cpetersky