The app is called WordService, so you could simply search for that. It
doesn’t didn’t come with an installation mechanism so far as I can tell, so you will need to find where you put it (or it ended up). The instructions suggest that changed with v. 2.8.1.
The instructions suggest
Simply move WordService into your Applications or Applications/Utilities folder or into the folder Services (in the Finder visit the Go menu with the Option key pressed; choose Library; locate a folder named Services; if there is none, you can safely create it manually).
so maybe the app is to be found in the /Library/Services folder?