The following short, unsorted list is far from being exhaustive
(how could it be?); the relative order does not imply anything about
the value of referred sites. Missing links will be added in the near
future.
TUG home page:
where you can find out almost everything about TeX
Gwaith-i-Phethdain: the Fellowship of the Word-smiths;
a rich site, full of interesting material, where you'll find also
the analyses of the short Elvish lines of the Jackson's movie
Mellonath Daeron: the Language Guild of the Forodrim;
among other interesting things here you can find the complete lists
of tengwar and cirth specimens
The Lambengolmor mailing list: a mailing list devoted
to scholarly study of the linguistic creation of J.R.R. Tolkien
Fabiano's personal pages: this site has nothing to do
with Tolkien's works, but my good friend Fabiano's site deserve a
link :-) Be nice and visit it sometime