Place your cursor in your story, and choose Window > Info to open the Info panel.
That will give you the story word count. If you have a lot of stories you can use Sandee Cohen's old trick of doing a find change for a space. Find the space and replace with one. InDesign will tell you how many changes it made.
If you are using OSX this AppleScript will get the document count:
tell application "Adobe InDesign CS6"
tell active document
set s to every story
set t to 0
repeat with i from 1 to count of s
set t to t + (count every word of item i of s)
display dialog "The active document has " & (count of s) & " stories, with a total of " & t & " words"
Jongware also wrote a script to do this, but works for indb files too. This was featured from the indesignsecrets.com forum:
You guys above are over thinking this haha. If you don't want to count the words for the entire document just highlight the text you'd like to count then Window > Info (f8).
Thanks for the tip.
Guys (I'm one by the way) ALWAYS have a tendency to over complicate things.