The National Archives now has online an 'index to the names of individuals entitled to enrollment on the rolls of the various tribes comprising the Five Civilized Tribes in Indian Territory (Oklahoma).' Names are arranged by tribe and alphabetically by surname in the enrollment categories. Entries provide the enrollee name and final roll number. Copies are available from the National Archives at Fort Worth, 1400 John Burgess Drive, Fort Worth, TX 76140. The cost is $15 per census card.