I'm sorry to hear that. The good news is, that the tutorial you follows seems to be outdated. The leJOS Eclipse plug-in is a much easier way of doing things.
I'm updating the tutorial right now. An updated version of the tutorial will be released soon.
In the mean time:
Install the plug-in from this update site: http://lejos.sourceforge.net/tools/eclipse/plugin/nxj/
. Then create a new leJOS PC project using File -> New -> Project. Put your code in that new project, and run your application using right click on project -> Run As -> Java application.