Dolly is an amazing GAL. C: And her hair tutorials are wonderful! You should definitely check her out.
I can't really help you with essentials/tutorials, but here are some gyaru blogs I've found that were pretty neat (and most of them have a "how to get started" post C: )
http://universal-doll.com/
http://chouzuru.blogspot.com/
http://utsukushiigal.blogspot.com/
http://pinksugarichig0.blogspot.com/
You can find more through their blogs. C:
I hope that helped! @~@