Great news!  On the About page, you can always find listed the tools which have been created for this project.  As of yesterday, Tech Support added Concordance-Reversed.py to the Digital Humanities Toolkit.

Concordance.py will take your text and strip out a set of Stop Words.  It’s what I used to strip out the Ten Thousand most common words from The Hobbit.

Concordance-reversed.py will strip out everything but a set of Go Words!  It’s what I’m using now to find specific lemmas, such as Fish, Fishes, Fish’s, Fishes’, Fished, Fishing.  Put all the different forms of your lemma into a text file of Go Words, and you’re on your way!

I love you, Tech Support, from your grateful Mama.