Even on Windows, I find it hard to think of a power user who isn't at least passingly familiar with the command prompt. I'd recommend either O'Reilly's bash sh

Even on Windows, I find it hard to think of a power user who isn't at least passingly familiar with the command prompt. I'd recommend either O'Reilly's bash shell book or 'classic shell scripting' which covers a bit more than just a shell like bash.