I use Cutterbees" brand scissors, which are the same as SU's paper snips. I got mine at WalMart. Also good are small embroidery scissors. Another possibility I've seen suggested: scissors used for making flies for fly fishing, which are sold at hardware stores and tackle shops. These scissors have teeth edges along the side so they hold securely.
Other helpful hints: Don't try to start with cutting right on the outline of the design. Poke a little hole in the middle of the design and cut away a small hole. Make several cuts, gradually moving towards the the outline of the design. Then cut the outline away in small sections. Move the paper, NOT the scissors! In some of the awkward places, it is easier to cut from below.
Hope that helps!
Linda