I would think an enamel spray paint...get some extra screw an run them up through a couple sheets of cardboard. Screw the knobs on these screws and then you do not have to worry about holding on to them and you can do a big bunch of them at once.
You can buy ceramic or glass paint at most crafts stores- or, do what I do when painting something slick with regular paint: spray it first with a matte finish polyurethane, paint it with your color and then spray it with your choice of poly (matte, satin or gloss) again a couple of times.
KMS's comment about the cardboard is good- or you can get a cheap sheet of styrofoam so the knobs can protrude a little more and you can get the bases & bottoms.
Thank you so much. I bough some handles but i was going to drill anoter hole in my cabinets . I dont want to do that if I can keep from it