Q: How to get my iTunes to recognize new files on my iPhone

Hello hlummus,

This can be achieved by using the 'Transfer purchases' functionality of iTunes, or by enabling 'Automatic Downloads' in iTunes for a more hands and cable-free approach.

1. Open iTunes.
2. If you have not already, authorize your computer for use with your Apple ID by choosing Store > Authorize This Computer. See this article for information about iTunes Store authorization.
3. For Mac computers: Choose iTunes > Preferences and click the Store tab. 
   For Windows computers: Choose Edit > Preferences and click the Store tab.
4. You can enable Automatic Downloads2 for Music, Apps, or Books under "Automatic Downloads."

Note: If the checkboxes are not selectable, you will need to sign in to the iTunes Store with your Apple ID.

iTunes Store: Transferring purchases from your iOS device or iPod to a computer

http://support.apple.com/kb/HT1848

iTunes Store: How to enable Automatic Downloads

http://support.apple.com/kb/HT4539

All the best,

Allen