Can anyone recommend Japanese post-grunge and alternative rock groups? Something similar to Linkin Park, SOAD, 3 Doors Down, Three Days Grace, Breaking Benjamin?

hmmmm.... Maybe RIZE falls into this somewhat?

(based off Linkin Park)

I'm starting to think that this genre doesn't even exist in Japan. You may like Hyde or Girugamesh...

I'm not sure what post-grunge is (if it has anything to do with Linkin Park, count me out!), but Japan is basically alt rock heaven. I recommend checking out this thread for some general recommendations (I consider over half of the bands I recommended in my post alternative), though your mileage may vary.

Thanks, I'll browse through that thread. Girugamesh and RIZE are quite good, actually.

I'm not familiar with these terms or the bands in question, can you describe the music you're interested in?