Want to include characters during in-game chat to spell things like "Nûrz Gâshu" properly?  Use 'Alt Codes'.

They work while holding down the ALT key and pressing the corresponding numbers in order to make the proper character text.

Here are the ones typically used in Lord of the Rings

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

A link to all the alt codes is available here.  (courtesy of Alt-Codes.net)