All I am asking about is posting a link to my sellers page on eBay. In
the rec.collecting.coins newsgroup, this sort of posting is very common
and does not cause any problems. The posting is listed as...FA coin for
sale on ebay...if someone is interested they look. If not, they pass it
by just like any other posting. Thanks again

It's not OK.

Suppose every person auctioning gardening-related stuff on
Ebay posted their auctions here? The newsgroup would die
under the weight of the advertisements. AFAIK, this is a
non-commercial newsgroup and doesn't allow advertising.

But you can have a reference to them as a .sig (signature)
file - that's accepted on newsgroups. When you participate
in conversations here, people will see the .sig file.

It would be best to refer to a web page that you put up -
and that page in turn can list all your auctions.

.Sig files should be preceded by two dashes and a space (as
the first characters in a line) and really shouldn't take up
more than four lines although a line or two more probably
wouldn't stir up much ire.

(See my .sig file as an example.)

Pat