I was certified to teach back in the day through the AHA. Try this American Heart Association page for a local search ...
CPR and Emergency Cardiovascular Care. You find a lot of FDs teaching them. To keep their teaching certification you have teach a couple classes a year. I would look for a fire dept. one if its available. Since they all want to keep their certification you will probably have five guys teaching the class vs. 1-2 at a private center. You may have to call the FD to find out. I don't know if they will show up on the search.
When I did it I had to pay an "official" training center $2 per certification card for each person I taught and $20 to rent the dummy and then charged what I wanted. I'm kind of rambling on here.........I think an FD will be give you a better course (more instructors) and be a bit cheaper.