Tellicherry pepper is a high quality black peppercorn grown in India along the Malabar Coast. Tellicherry pepper is the pepper used whole in salami making. The heat from the pepper comes from the volatile oil, piperine and resin. Tellicherry pepper is typically sold whole so the user can grind it as needed but you can find it ground as well.
Look for tellicherry pepper in higher end cooking shops (Like Williams Sonoma) or very well stocked grocery stores. Costco sells it in their spice department. It can be easily had online at Amazon.com: Tellicherry Peppercorn