First, a small digression… :)

I’ve gotten this question (”How do I move the ToC to the end of the post?”) a couple of times now, which means that I’ve made the interface too complex. However, I can implement the old/simple interface in terms of the complex interface, and then give an option for users to either use a “basic” or “advanced” interface. I filed bug 22 a while back for just this purpose. Hopefully, this will make life a lot easier for you down the road (though it isn’t much help right this instant).

Now, to answer your question:

1. From the WordPress admin pages, go to the “Options” tab and the “Series” sub-tab
2. Look at the value in the “Post layout” field
3. Move the %content token from the middle to the beginning of that field
4. Click the “Update Options” button.

The %toc is where the table of contents will go, and the %content is where your post’s text will go. Just make sure that the %toc comes after the %content.