The Official Ju-On "The Grudge" Website
this link is for the first movie, and via a movie, briefly tells the story
Ju-on: The Grudge 2
this link i highly recommend cuz it talks bout both ju-ons and the english version and explains why so many scenes were deleted from the english version that were kept on the japanese version
and since 'Ringu' (The Ring) was produced by the same people, and you enjoy those movies, you should check these links out.
Ringu / Ring
this link is like the other mandi apple. it shows some snippets from the movie, some screen shots and explains the fame and how popular it was in japan. this link is for Ringu one.
Ringu 2 / Ring 2
first of all, i dont rele recomment ringu 2, cuz its kinda a repeat, but if u are interested here is the same mandi apple site with everything you need to know
The Ring Cycle - Visual comparison of the 3 movies
and heres a link comparing ringu with the english version, the ring (interesting)