I've been following these guys for a year. They sometimes have a harmonica player with them, but usually it's just the two of them at their gigs. Following in the R.L. Burnside trance/punk blues style, natives from portland.
The thing I love about Hillstomp is that they ALWAYS have killer bands opening for them as well. The show they just had at mississippi studios was incredible with this band opening:
yeah Michael, they rock. I think the harp player you are referring to is David Lipkind who also plays with Joe McMurrian. Now that band has this planets best blues drummer in Jimmy Bott. Pluto