I thought this anime was incredible! I think it really opens you into the world of madness, identity, and discernible reality. That being said, I didn't find it very Hitchcockian just because it is more than just a suspense thriller/mystery and Hitchcock really didn't deal a lot with perceptions of reality and obsession.
I'm not familiar enough with Argento's work to really comment on his classic themes, though I didn't find this very David Lynch. There are several allusions to Lynch's Mullholand Drive, but from what I've heard about the plot in Inland Empire, it follows Perfect Blue's plot and themes much closer than Mullholand Drive.
Here's Inland Empire:
http://www.imdb.com/title/tt0460829/