Here is how you can find an Avery template in LibreOffice:
From the Menu bar at the top, choose File > New > Labels.
From Brand select Avery Letter Size
For Type select your Avery template number
Then select New Document and a blank template will load onto the page
Note: not all templates are available in LibreOffice
Avery does not currently offer the .OTF or .ODT template type. However, our downloadable .doc templates for older versions of Microsoft Word work well with OpenOffice and LibreOffice. Avery Design & Print Online is a great solution for OpenOffice and LibreOffice users. Visitavery.com/templates to find a template or to use Design & Print Online.