<Edit on 7/26/2013> I'm pulling this for now while I troubleshoot. Thanks for the reports and sorry for the noise.
I finally got a few minutes, and more importantly, a computer with everything I needed to build, free and updated the text importer for OneNote 2013.
There is almost zero change from the 2010 version - I just used to old 2007 version and updated it - so I won't repost any directions here. And the code is unchanged as well - I only updated the schema and COM references to OneNote 2013. Just copy this file down and change that last underscore character to an "e" to get it to work. There is no install program.
Questions, comments, concerns and criticisms always welcome,