I am currently building a Tesla coil.  Do you have any suggestions where to source materials and components such as high voltage power supply transformers?

Visit a local neon sign shop for your power supply transformer.  The electric utility company that services your area might also be able to provide you with a high tension transformer or at least point you in the right direction to obtain one. 

Some additional suppliers are:

   • Batteries 
       • Batteries.com 
       • Batteries 4 Everything   
       • Only Batteries   
       • Rayovac 
   • Capacitors
       • Cornell Dubilier mica chip capacitors 
       • ITW Paktron 
       • Jennings Technology 
       • Maxwell Technologies  
       • Stormwise (air variable)
   • Copper Wire
       • MWS Wire Industries 
       • Paramount Wire Co. 
       • Rea Magnet Wire Company, Inc. 
       • Superior Essex Inc. 
       • WireTronic Inc.  
   • Electronics Components
       • Allied Electric 
       • American Microsemiconductor 
       • Antique Radio Supply  
       • Arrow Electronics, Inc. 
       • Circuit Specialists 
       • Cross Components, Inc. 
       • Davilyn
       • Dick Smith Electronics
       • Digi-Key Corporation, Catalog [.pdf]
       • Electronic Surplus Inc. 
       • Fair Radio Sales Company
       • Jameco Electronics 
       • Kreger Components, Inc. 
       • M.A.T. Electronics
       • Marlin P. Jones & Assoc. Inc.
       • MECI
       • Mouser Electronics, Catalog [.pdf]
       • National Semiconductor, Power Electronics 
       • Newark Electronics 
       • ON Semiconductor 
       • Radio Shack 
       • Richardson Electronics (Snubber Caps)
   • Electro-mechanical Components 
       • CUI, Inc. 
       • Herbach and Rademan
   • Ferrite Cores 
       • Amidon, Inc. Inductive Components, Rods 
       • Alpha Core, Inc. magnetic cores & specialty wire products 
       • CWS ByteMark, Rods
       • Fair-Rite Magnetics (Type 78 Ferrites) Catalog 
       • Stormwise 8.125" x 0.485", 3.4", 5.6", 12.45" & 24.75" x 1.12"
       • Surplus Sales of Nebraska -- The page cannot be displayed
   • Front panels
       • Front Panel Express 
   • Magnets
       • ForceField 
   • Materials
       • Goodfellow 
       • McMaster-Carr 
   • Printed circuit boards
       • ExpressPCB
   • Prototype board (perforated) & flea clips
       • Vector Electric, Vectorbord 
   • Transformers, High Voltage
       • T & R Electric Supply Company, Inc. 
       • Additional Transformer Suppliers 
   • Toploads
       • O.W. Landergren., Inc. 
       • Sparks and Arcs!!!!