ITX Corporation ITX Corporation is an energy production company with offices located at 3838 Oak Lawn Avenue - Suite 1600 in Dallas, Texas. Our mailing address is P.O. Box 25202, Dallas, Texas 75225. Contact Information Our telephone number is (214)363-1955 and our fax number is (214)522-2129. General email address is itx@itxco.com. To Report An Emergency Please call toll free 1(800)880-1955.