http://wccftech.com/download-itunes-1263-windows-mac/

You can now download iTunes 12.6.3 for Windows (32-bit/64-bit) and Mac with built-in App Store for downloading apps and games.

With the release of iTunes 12.7 some time back, Apple ditched the App Store altogether on the desktop. This meant that you can no longer use iTunes to search for and download apps or ringtones if you wanted to. But this change (apparently) did not bode well with certain consumers and businesses who rely on iTunes to deploy apps. This pushed Apple to release a new version of iTunes, which sits at version 12.6.3. It brings back the App Store, and once installed, you won’t be prompted to install newer versions of iTunes, if they become available in the future.