Looks like Apple is making an effort to slim down iTunes. The most recent update mentions that your apps will no longer be managed in iTunes. You need to do that in the mobile device App Store.
I have a few homemade ringtones and was wasn’t sure how I’d be able to create new ones, but looks like there is still a way to do so (for now). Check out the Apple support page HT201593 to manually manage content on your mobile device and this one specifically for ringtones..