Q: I recently upgraded my macbook to Mountain lion.  Before doing so I used time machine and an external hard drive to back up my entire laptop.  When we upgraded my computer came back like new. All pics, music, videos documents etc gone.  How do I get them

I recently upgraded my macbook to mountain lion.  Before doing so I used time machine to back up my entire laptop with an external hard drive. 

When I got my computer back it was clean....all pics, music, documents, bookmarks etc. are gone.  How do I get these files off the external hard drive and back onto my laptop with the new upgrade?