About The Castleberry Group - Sonic Amarillo

David Castleberry received his first paycheck at age 13 and it was signed by founder, Troy Smith at Sonic’s first location in Stillwater, OK. That piqued David’s interest in the fast food industry far beyond the typical teenager’s work experience. He formed the Castleberry Group in December 1975. He and his brother Roger expanded the group to the Amarillo market in 1990 and it has grown to 34 stores in Texas and Oklahoma.

We strive to provide a professional working atmosphere and are dedicated to employees to help them reach their goals. We aim to provide fast service, quality food and exceptional customer service each and every day. The opportunities individuals have had greatly contributes to the overall success of the company. The longevity employees have within our company has proven that we view our employees to be as important as a new customer.

The Castleberry Group’s commitment to excellence includes employee and management development.  The tenure of the employees has greatly contributed to the overall success of the company, and proves that the group truly views employees to be as important as the customers they serve.

Administrative Support Team

Andrew Irick
Director of Operations
Since 2020

David Hemphill
Chief Financial Officer/Partner
Since 2007

Camie Boone
HR Administrative Director/Partner
Since 1997

Paige Hadley
Supervising Partner
Since 2013

Elizabeth Rush
Since 2019

Texas Market Supervising Team

Daniel Arganbright
Supervising Partner
Since 1996

Greg Costello
Area Supervisor
Since 1996

Jeff Meador
Area Supervisor
Since 2001

Tony Summerall
Area Supervisor
Since 1999

David Tapp
Area Supervisor
Since 2000

Oklahoma Market Supervising Team

Lonnie Bardwell
Supervising Partner
Since 2013

Rhett Garvin
Supervising Partner
Since 2013

Sandy Oshman
Area Supervisor
Since 2021

Recent Awards

  • Brand Leadership Award (Presented to Roger Castleberry in 2021)
  • Top Ten Sales Volume
  • Brand Development Award
  • Local Store Marketing Award
  • Turnaround Market of the Year Award
  • Troy Smith Award (David Castleberry was honored with Sonic’s prestigious top award in 2001)
  • Highest Rating for Convenience
  • Best Small Companies List
  • Top Restaurant Chains
  • Top Burger Category Award
  • Best of Amarillo recognition for Best Fast Food Restaurant, Best Happy Hour, Best Onion Rings and Best Fountain Drinks