Mention your name and a short description of who you are. A credit card authorization letter gives someone permission to use your card.Learn how to write one, and when it's appropriate to use it. Contact your bank for a power of attorney form. Make checks payable to the Illinois Secretary of State. Chicago, IL 60686-0068. All forms below with a "fillable icon" are documents that you can open "on-line", fill in the appropriate fields and then print on your printer. Corporate offices: (Not open to the public. No branches or ATMs.) 11545 W. Touhy Ave.