Paisley, Mayer, or White.
Listen to what mayer says around 3 minute mark. I am a huge mayer and white fan, but they aren't in the same ball park as trucks. He has pretty much reinvented slide guitar. Can't say much about paisley as I don't listen to too much of his stuff.
Edit- Don't know why frusciante was chosen to sit next to the likes of those two
This post was edited on 4/23 at 8:15 pm