Yes, I did (this is what I started with). When you Goggle "Drool", the top in the list is "Drool - JBoss community" link where you can get link to "Documentation". Over there there is a link to manual, but I don't see any link to beginners tutorials. The link that I found for tutorials, doesn't contain source code. This is what is not clear for me - if there is an active development of a tool, but there is not much recent activity around this tool in Java world, then the question is if people are still using this tool. That's why I am looking to hear about other developers experience with different rule engines.