The Stephen Foster Citizens Support Organization (CSO), a 501(c)(3) not for profit organization, has been dedicated to the advancement of the park and its activities since 1988. Join us today by completing the application information below. We accept Visa, Mastercard, Discover and American Express. If you wish to pay by check, please complete the application and mail your check to: Stephen Foster CSO, PO Box 666, White Springs, FL 32096. Please include a note that you completed your application online so we can activate your membership. If you wish to pay by credit card and not enter your credit card information, please call 1-877-635-3655.