Just to clarify with people who may stumble on this:
I was originally looking for a plug that will split a PAGE according to word counts. However, it seems this is not something that can be done so I've now abandoned the idea.
I'll be using POSTS for what I'm trying to do. My goal is to find a way - or plug - that will automatically add the <!--nextpage--> tag after every so many words. I'm using WordPress to present a book - so having the ability to just past my content in a post and hit 'publish' and have everything automatically parse correctly is a very big deal. I don't have a lot of time to screw with formatting each post everytime.
If I have to, I will obviously make the extra time (which really isn't a huge amount).
So, if anyone has any ideas how to have something add a line of code after so many words, that would be great!!