Material Vendors
Here is a list of some of the more common suppliers for call making stuff as well as some more generic types of outlets that worth checking out when you're in need of something.
Call making specific tools, parts, etc...
Aside from our site, where you are right now :D - there are many places that now sell call making related items. Hitting the ole search bar will likely yield some good results. We know that we do not carry everything everyone will need or want - so our intent is to help you find what ever that item may be that we might not carry.
Deadshot Polymers sells not only a large variety of Cast Acrylic rod, but also Acetal and Ebonite. And to add to that, they also carry bands, call bags, and a few things like reeds and cork. Not to mention, Brian and Chris are darn good guys.
RiverMallard carries mandrels, some "public" and a flat jig, along with bands, call boxes, wood blanks, and some other call making supplies. Doug is great to deal with.
There are many others, and a web search will turn up a bunch of sites. Probably ones we don't even know about.
Call blanks and material...
Acrylic - Deadshot Polymers, Delvie's Plastics, Midland Plastics, etc... Deadshot Polymers is the sole US distributor for their line of cast acrylic. The rest are distributors of Spartech's cast acrylic rod. We try and use Deadshot Polymers as much as possible due to the reasonable pricing, great customer service, and larger variety of material.
Acetal/Delrin: Deadshot Polymers and Midland Plastics
Ebonite: Deadshot Polymers
Acrylic Acetate: Beartooth
Wood: Ooophh... that is a material that we just do not keep up on. There are many wood suppliers out there and a web search should turn you on to a bunch of them - and the various FB pages etc should help you identify any that really stand out.