I was happily making nut butters at home until I burned out the motor of my blender... I now have a machine that's sold for the purpose, but the capacity is small. I recommend a store where you can grind your own peanut butter from organic redskin Valencia peanuts. And when you find one, let me know where it is. I haven't had it since the store we owned, closed 2002 -- best ever!

Not much help here, but I have not had luck making nut butter in either my food processor or blender (both "better" kitchen aid appliances, not the cheapest ones) but my friend can really plow through the nuts with her Vitamix. If you can justify purchase of one of those, that is the way to go for blending and grinding. (they have them at Costco from time to time.) I have been lusting after one of those and eventually I will go for it.

You might find that a blender does a better job making nut butters than a food processor. It does for me: I get a smoother result in less time with the blender. It depends on the capacity and power of your machines.

The method is the same either way; the blog post describes it well.

There's a great post on making homemade nut butters here: http://www.food52.com/blog/3645_homemade_nut_butters The focus is on almond butter, but the same method works with peanuts.