The iStory Creator is an application that can be used for creating interactive stories that can be uploaded and read on iPods, but I believe there is a way to run it as a computer program as well. Here’s the link:
http://www.softpedia.com/progDownload/iStory-Creator-Download-21036.html
It might look a bit intimidating at first, but the program is actually really easy to navigate once you get the hang of it. Basically what you can do is create a number of different pages with text, and link them together in any order. When it is run on an iPod, it works is very similar to a CYOA book. The text appears at the top of the page, and the different links appear at the bottom.
I haven’t really explored what limitations there are in terms of text/page limitations. It does look like there is a limit of 18 links per page, but I can’t imagine that being a problem.
I’ll upload any other information as I find it, but feel free to make corrections/clarifications/suggestions.
*A cool feature that this program has is that when run on an iPod, sound can be added to each page. This could be pretty cool if combined with sound effects or spoken word tracks, and obviously music as well. The only problem is that I don’t think this is an option if only run on the computer.