There is one at the very top on that site called "Notice", there you can find the self-introductions. It's the old ones, since for example Shiori changed hers. But she has only changed what she says, so the chants themselves are the same.
No, I'm afraid not. I would love to see a site or something that has chants for the newer songs, like most of 5th Dimension and onwards. I've always wondered where the chants are agreed upon? Is there some Japanese fan forum where they discuss this? But even so, how does it get out so that EVERYONE knows them?
I asked myself that when I saw fans in LOS ANGELES knowing the girl's introduction during Anime Expo. Then again, it's possible that those specific fans were either from Japan or have a Japanese heritage in their family.