If you're using a typical headset, IMO it's one part that really doesn't need bike specific tools. I use a brass drift to knock out cups and crown race. Threaded rod, nuts, and washers to press new ones in. A piece of copper or PVC pipe tp drive on new crown race. Probably the most important tool is a caliper to measure things so you get the right headset as far as cup and race diameters, stack height etc.