Want to include characters during in-game chat to spell things like "Nûrz Gâshu" properly? You can use 'Alt Codes' for this. (hold down ALT and press the corresponding numbers).

Here’s a list of the most commonly used symbols within Middle-earth literature, along with the codes required to type them.

 
ALT-131    â
ALT-160    á
ALT-132    ä
ALT-137    ë
ALT-161    í
ALT-148    ö
ALT-147    ô
ALT-162    ó
ALT-150    û
ALT-163    ú

For more symbols and alt codes, you may find them here.