I bought a dozen "capri" prefolds from Little Lions. I went with that size as I knew the regular ones would be too big and bulky. The measurements are almost identical to GMD's old rainbow-edged prefolds, which I think are the perfect size.
Of course, I had to dye them. Can't have boring white diapers, now can we? I went with amazon green, tropical green, and sunflower yellow.
I took pictures of the whole process as well, which I'll post along with a tutorial for those wanting to give it a try. :)