It's not there in Poser 7--just the higher version.  You just bought, Poser 9, right?  You don't need to do anything to your libraries in Poser 7.  This is the Library tab from Poser 9.  When you click on the little folder with the + and the running man (bottom right edge of dark area), you can navigate to the Poser 7 file in which your runtime is located.  Don't link to the runtime folder, but to the folder up one step (probably called Poser 7).  Then, when you click on the drop arrow next to Show Library:  (to the left of "Dawn" above), it will show Poser 7 (or whatever the folder is named) as a choice.  That will make all your Poser 7 content available to use in Poser 9.