We bought it at Bamboo and Rattan Works on the east coast. They are on the web. If you talk to them and tell them you want the stuff they use for kids bows, they'll know what you want. We tillered one to 50+# at Cloverdale one year. The normal build tools are a band saw and a belt sander but hand tools can and have been used. Here's the pic.
As I posted on another site, I planned on making a rattan warbow for MOJam one year, but I got the full length poles from another supplier and they were bruised all over. Bruise=hinge on rattan. I never ordered more, so who knows if it wouold have worked???