RE: How to build actuators
There are a lot of workable techniques. If you want to experiment you can start by harvesting the wire from Radio Shack's smallest relay. You can just wind on a straw putting a tiny bit of glue on the wire as you go. Done freehand with no washers on either side you will not get a nice looking result, but it will work.
I started out with coils from Dan, made some test freehand ones, then graduated to making smaller remote actuators at 0.4 g each. There were a lot of steps in between. Good luck.