Where can I find these videos?

Question:

Does anyone know where I can download PVs by Perfume? (Not torrents)

I can't seem to find non-subbed versions of them anywhere.
There are really only 4 I reallly want;

Chocolate Disco,
Natural ni Koishite,
Nee
&& VOICE

So, even if you would know where I could find those 4?

I'd appreciate the help :)
♥

Answer:

Chocolate disco: http://www.youtube.com/watch?v=5JjV71fWq…
Natural ni Koishite: http://www.youtube.com/watch?v=edyARJq9s…
Nee: http://www.youtube.com/watch?v=OPE9-pReM…
Voice: http://www.youtube.com/watch?v=18grnTXq7…

Please post another question if you don't know how to save the youtube's videos locally.