Where can I find 動画 for rosario vampire season 1?

Either youtube, または google: bittorrent rosario vampire.

Well if registered on bleachexile あなた can download them :)

animefreak and veoh have good quality vids

sky7anime.net または voober.com.there are some episodes on YouTube but incomplete so i suggest to あなた those 2 websites.both 2 websites have complete episodes of the series.

Funimation (free if not expired)
Netflix (paid)
YouTube (free)
Crunchy Roll (paid)
または if あなた look it up on Google there should be some English dubs available for free