In an older version of word, I used to be able to preview a doc when searching for a doc that I can't remember what I saved it under.

In my present Word I an not able to do this.

How do I preview a doc without having to open it and go through the whole rigamaro of reopening Word everytime?

Click Open and (in Windows 7) the button to turn on Preview Pane is in the upper-right of the dialog box. It's under the Search box and to the left of the Get Help (Question mark) button.