Talend open studio cookbook (by Rick Barton)
This is an excellent book for beginners. It starts with explaining contexts, generic schemas and others and give examples of how to use these. Futher book goes into different components available in talend and give examples of their usage.
Important points are mentioned across different sections of book.
Steps to unhide tHashoutput/input components are also mentioned.
I found book a good read.
Link to book - http://www.packtpub.com/talend-open-studio-cookbook/book