[impendia]

Yes. The Yamanobe Road is easier to get to, the endpoints are each close to train stations (Tenri on the north end, Sakurai on the south). These are well connected to Nara and Osaka. Alternatively, you can start at Sakurai and walk all the way north to Nara (about 30 km).

The henro-michi is harder to get to, because Shikoku in general is harder to get to. If coming from Kobe or Osaka, you'll probably want to take a bus to Naruto, Tokushima, or Takamatsu. (Naruto if you're starting from the beginning.) A bit more of a schlep, but still not bad.

If doing these walks, then not driving is a big advantage -- because you don't have to worry about where you parked your car! In particular, you don't need to end at the same place you began.