Fundamentals of Bash Scripting Link
Nettuts does a really good job with these mini-tutorials. The latest about bash scripting is true to their record. What makes this one standout is the form. It starts with a premise and works through the increasing complexity step-wise.
It turns out that 90-99.5% of the candidates for a programming job are simply unable to write the simplest program. Imran took this simple Fizz-Buzz game and asked the candidates to solve it.