Guide for users, programmers, technicians and service providers.
Ubuntu Unleashed is nice book. Bit expensive compare to the information you can get online regards to troubleshooting, tweaks and settings of Ubuntu. I bought it for myself and it made worth during the course of time. Many things are mentioned in the book more systematic way compare to anyone searching for those answers online. If you are a fan of Ubuntu or truly giving services via Ubuntu, this book will be handy.