Do you mean "Microsoft Office Picture Manager"? If so then if Microsoft Office is installed then it should be in the start menu under Microsoft Office\Microsoft Office Tools.
Though if your goal is to organize photos then I think Windows Photo Gallery would be a better choice.

I'm guessing you mean that the "Picture Manager" shortcut isn't there as there are always shortcuts in that folder.
In which case if you have the Microsoft Office install disc you can use it to install the Picture Manager componet.
Also to be clear, you are talking about the one listed at http://en.wikipedia.org/wiki/M.....re_Manager ?

Ok, in that case I think the path is C:\Program Files\Microsoft Office\Office11\OIS.EXE
Note: Path will vary if you installed Office to a different place then C:\Program Files\Microsoft Office.