Seeking recommendations for GC license prep course

[Chris Harjes]

I'm looking to get my NC GC license to open up more options as a flipper- does anyone know the best online/audio source for learning the exam material, or the best way to go about it? I do a ton of driving, so CD or Audible format would be best for me if that's an option.  Looks like tons of courses out there, but I have no way to know which are legit/worthwhile.

Thanks y'all!

Chris