When I want to catch really small sunfish I break out my fly rod. The biggest impedemnet to catching the little guy's is normally hook size. Even a number 10 hook can be hard for small sunfish to get their mouth around. I'll tie some small nymph or sow bug type flies in size 16 or smaller barbless hooks. I fish the nymph suspended about 12 - 14 inches under a popping bug. If a fish even thinks about looking at that nymph he'll get hooked by that little 16-18 hook. The nymph doesn't have to look like much for sunfish, just a little dubbing, or yarn or peacock herl wrapped around the hook with a little bit of a tail sticking off will work.