If your are looking for yourself/small quantities - you want a retail flour/grain mill.
If you are searching for a commercial solution - be sure to locate a mill with actual milling stones or that has a hammer mill. Operators that grind spices are an option.
For actual Turkish Coffee, you want to be able to make a coffee "flour", so grinders (small technology) and granulizers (large technology) won't generally deliver adequate results...even though some will insist that they can.
Are you enjoying Barista Exchange? Is it helping you promote your business and helping you network in this great industry? Donate today to keep it free to all members. Supporters can join the "Supporters Group" with a donation. Thanks!