For what it is worth, I just started the Heads First Servlet and JSP book as well. I am running Fedora with tomcat6. I got the example to work by creating a directory called WEB-INF and a classes subdirectory in WEB-INF. I copied the web.xml file into WEB-INF and the Ch1Servlet.class to WEB-INF/classes/. My web.xml was: