Normally in the rails community it's published in blogs (our own
blogs). It's highly recommended that you start one...this way if the
article is good the rails envy guys (http://www.railsenvy.com/) will
track you and talk about it in their podcast (which will spread the
word through the rails world).
Also there's this new magazine (http://www.therubyist.com/) that's
calling for papers...