The tools for scratchboard can be almost anything sharp. However, I personally like to use X-Acto blades (#11 is my favorite, and it's very easy to find that blade in stores and online). You can also buy a Scratchboard tool kit at Dick Blick that has a series of tools. Honestly, the only one I use very often from that kit is the fiberglass brush. But, everyone likes something different, so it might be a great place to start. I know that many scratchboard artists love tattoo needles and also scalpels - I've yet to try either one, so I'm not very helpful in that regard. I hope you give scratchboard a try! It's pretty addicting!