I played the ETN demo a few months ago and I believe it exists on its own server. The tutorial zone is available on live servers, but characters there can't interact with trial account players.
Actually, with the Steam holiday sale going on now, your friend might want to just get the $5 Seeds of Destruction pack with the free month of gameplay - then you could play together and not worry about the demo restrictions.
http://store.steampowered.com/app/24130/
Edited, Dec 30th 2009 12:08am by Samatman
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