Hi, The electornic bill boards that I am looking for is the ones where
you can display them in city's square an example of that would be
"Electronic-Digial bill boards that are in Piccadily Circus in
London"! I want to find the same ones at second hand at low prices. If
you can find me the sellers please let me know... thank you. Just to
remind I am not looking for (Led electronic boards) I am looking for
the ones that display quite clear image, similar to a plasma TV but
not exactly plasma because they would be expensive!!!, or the ones
that are in Central Time Square in NY, where you can see images and
adverts like on TV!!! THank a lot i will be looking forward to your
help.

What I think you are looking for are LED videoboards. There is a
German manufacturer leuro.com. If you visit their website at
http://www.leuro.com/english/index.html

and click on Products ... Applications ... Advertising or Products ...
Applications ... Sport you can see examples. There are also details of
projects they have done under References ...

They are not going to be cheap, and because they are usually
manufacturered to fit a site you are unlikely to find many
second-hand.

Owain

I've also seen this article you might find interesting
http://www.signindustry.com/led/articles/2002-07-30-LBledBillboards.php3
There are some nice photos of LED advertising boards.

Owain