Hello,
Have to remember that Office is not a program, it's a folder containing the Office applications, like Word etc. When you install Office 2010 or 2013 in Win-8, it will place the individual applications as a tile on the start menu, or in the all apps screen.
There you right click, pin to task bar, and away you go.
You can create a shortcut of the application itself, but you have to locate for example Winword.exe, and creat a shortcut from that exe file to the desktop and then the taskbar.