The first two volumes are the only ones that have been translated into English editions, by humanoids publishing and later by dc comics. The other two haven´t been released as English editions yet.
Yes there are a few, try deviantart they have some ulquihime doujins XD but they're not videos they're comics XD but if you ask me i prefer reading the comics online rather than watching XD this one...
To the best of my knowledge, as of February, 2011, "Les Ames Fortes" has not been translated into English. If it has been, I can find no record of it. Many of Giono's works have appeared in English,...