So a while back I learned that it's now preferred to put one space after periods instead of two. I filed it away, and continue to use two, because let's face it, it's hard to teach old dogs new tricks. Habit takes over. My thumb just plain hits the big bar twice.
But thanks to a life-changing (or at least really important) post by Writer's Block Admin Services (credit to Robert Chazz Chute for providing the link), I learned that this problem is very easily solved. In Word, using the replace feature, in the 'find' box you type two spaces. In the 'replace' box type one. Hit 'replace all'. Wham. Done. It's that easy.
Sure makes me feel dumb for dreading the task of deleting them all one by one.