I purchase audio books and cant find them, how do I sync my audio books and view them in the new os7. I use to go thru music?

They are still accessed via the Music app, if you have audiobooks on your iPad then you will get an Audiobooks option at the bottom of the Music app, possibly via the More button. If you can't find them in there can you find them via the spotlight search screen (pull down the centre of the home screen in iOS 7, though not from the very top of the screen) ?

If not then do you have them in your computer's iTunes library and/or on your backup of your downloads/library so that you can sync them back to your iPad ?

The HT5085 page that you posted from, about what can be redownload where, doesn't apply to audiobooks, they are one-time downloads.