There are over 200 fake languages

These are the languages made up of books, TV, or film. Klingon is one of these languages.

Quenya. The High Elf from 'The Lord of the Rings' is the king of the list in his own right. Invented by Tolkien when he was barely 20 years old and developed over the next 20 years until the publication of his magnum opus, the Elvish language traces its roots to Latin and Finnish. There are published books (even in our language) on how to learn it and thanks to its popularity it is easy to find abundant information about it on the net. A good starting point is your Wikipedia entry and your list of external links. More information on Quenya – The Ancient Language.