VIZ just issued a press release announcing that the first season (13 episodes) of InuYasha are now available on iTunes-- hopefully they'll churn it out at a good enough clip that iUsers can get caught up on the show by the time the new InuYasha anime starts coming out (simul-release, VIZ! Pleeeeease!).
The first episode is currently available for free exclusively on iTunes, and you can buy the 13-episode series for $22.99, or individual episodes for $1.99 each. And yes, more episodes will eventually be added. There's no option for dub or sub, so it's safe to assume that these are dubs.
I'm downloading the first episode right now-- it's been a long time since I watched any InuYasha. As with most of Takahashi's longer series, I really enjoyed the show, although I never felt the compulsion to watch every single episodes. How about you?