Q: Somehow I've split my Itunes library, and when I try to sync, I'm prompted that the device is synced to another library on the computer.

Hello 1redruM,

I understand that you might have a split iTunes library. Let's see if we can figure out how to fix that.

I would start with quitting iTunes. Once you have done that, hold the Shift key and start up iTunes. You should be treated with a dialog box to choose your iTunes library. Locate and select the one that you think your iPod touch is using and you will be good to go. More details outlined in the first article. 

Open a different iTunes Library file or create a new one
https://support.apple.com/en-us/HT201596

As far how to consolidate your library, look for the iTunes folder in you My Music folder. Because you have two libraries, pay attention to which one you are looking in. To get that content to the correct library, all you need to do is drag and drop the music on top of iTunes to begin importing it. Once that is done and organized, you should be able to delete that content as it should be copied to your correct library. Take a look at the next two articles for more information.  

Locate and organize your iTunes media files
https://support.apple.com/en-us/HT204668

Import music and video from a computer into iTunes
https://support.apple.com/kb/PH20507​

Look over each article and let me know if you need further assistance on sorting this out. 

Take care

Hey 1redruM,

While you can start over by reinstalling iTunes, you should still be in the same situation as far as your music being everywhere but where it should be. So that is not going to be a good idea. 

Probably the best bet is going to start a new iTunes library, setting up the location of where you are going to store the music and finally importing everything in. Take a look at the links that I already provided that can walk you through those steps. 

Make sure that you have the location set and check the box that says Copy items to the iTunes Media folder when adding to the library. This will make sure that you items are organized.  Once the import is complete, you will want to delete the previous files. 

It is this option or what was previously stated of finding the right iTunes library to add things in. If you start new or choose a library you are still going to have the prompt that your iTunes library was synced with another computer. You will need to sync it but don't worry about losing content as you will already have it in your iTunes library after consolidating it. 

Take it easy