General Tolkien References:
Tolkien Gateway: another Wiki"What Tolkien Officially Said About Elf Sex": "A cross-referenced list of everything Tolkien said about elf sex. Rated PG, with actual footnotes and bibliographic references."
Ardalambion: the languages of Arda
Real Elvish Phrase Books: Very accurate useful phrases.
And their own list of Trustworth Tolkien websites
and Untrustworthy "Tolkien" websites
Quenya Lapseparma - The Quenya Baby-Name Book: original, grammatically correct Quenya names
Avoid Grey Company (http://www.grey-company.org/Circle/language/phrase.htm) and sites that copy from them. Although this contains some words from Tolkien's elvish languages (Quenya and Sindarin mixed together), it is basically an invented language for D&D gamers and similar purposes.
Mary Jean Holmes: really good fan fiction, including some set in Fourth Age Blessed LandsRole Play:
Fellowship of the Fourth Age (archives 2009-2013)
Fellowship of the Fourth Age (new site)