The greatest obstacle for me was knowing which tools did what. Many things I wanted to do in the shell I did not know were possible, and even Google is of limit

The greatest obstacle for me was knowing which tools did what. Many things I wanted to do in the shell I did not know were possible, and even Google is of limited value when your query is necessarily vague, though this has gotten a whole lot better in recent years. Have an IRC connection to Freenode open so you can ask about these sorts of things that are more easily understood by humans (#bash, ##linux, ##workingset are good channels to be in). If you're really lucky, you have some knowledgeable mentor around who doesn't mind you asking them about the best way to perform some task (I was not so blessed).