www.customcalls.com

If it deals with making calls.... you'll find information there. There are some true masters of call making that frequent their forums. If you need materials or advice to build it yourself, you'll find advice and links to sources there. If you just want to purchase a custom call at a fair price, there are plenty to choose from and contact info for each.

I'm contemplating a Pat Strawser glass call myself. I have his contact information... just need to pull the trigger.