I'm not sure what exactly "it" is that is saying you can't get anything or already have everything, but you can get X3-compatible tones from Customtone (see link at top of this page). Select X3 as the product and tick the box to indicate that you want to see all compatible tones. This will include XT-based tones.

Here's a video that explains it all:

http://line6.com/community/docs/DOC-2066