Below you will find references to different site that can get you started. Enjoy the Tableau journey.

Free Training Videos by Tableau
http://www.tableau.com/learn/training (link)


User Reference Manuel
http://www.tableau.com/support/manuals/quickstart (link)


Step By Step Get Started with Tableau DesktopĀ 
Learn how to connect to data, create data visualizations, present your findings, and share your insights with others.
http://onlinehelp.tableau.com/current/guides/get-started-tutorial/en-us/get-started-tutorial-home.html (link)


Tableau Starter Kits (8 sections)
Practice authoring, interacting, publishing, and administering Tableau.
http://www.tableau.com/learn/starter-kit (link)