There is a document from 2006 http://docs.jboss.org/jbossas/guides/installguide/r1/en/html_single/ that describes using a GUI to select options for installing JBoss. However, I’m unable to determine where the contemporary version of the jems-installer-1.2.0.jar mentioned in that install guide is found.
The wiki at http://community.jboss.org/wiki/JEMSInstaller provides links to passworded SVNs only; whatever it’s discussing is nowhere to be found on the public SVN.
A blog post at http://www.ericgar.com/2006/10/17/eclipse-jbossas-ejb-30-setup-instructions/ provides a direct link to Sourceforge where there is an installer jar: http://prdownloads.sourceforge.net/jboss/jboss-4.0.4.GA-Patch1-installer.jar?download.
Does this utility simply no longer exist?
Here you go:
Although it looks as if the project was abandoned around 2008ish. It should support JBoss 4, possibly 5, but not any later editions from what I’ve read online.
Personally I wouldn’t bother with it, installing JBoss is pretty simple – and getting to know the config files will help you later while you’re administering it.