the first time hurts the worst when you pluck them, once you go back and do the hari thats re-growing in, I guess it's not rooted as deeply or something like that, it doesn't hurt nearly as much. In fact, I thinkies I have a slight problem in that I love doing my eyebrows because it feels cool.
as for a totally pain free way, I don't think there is one. I mean, if you fixed it with a razor I suppose it wouldnt hurt, but that's not very accurate and it grows back fast with little stubble and it's just bleck, I wouldn't recomend it.