I have treated a multitude of patients with plantar fascitis. Chiropractic manipulation of the feet is very important in the recovery process. As a matter of fact, my entire protocol for plantar fascitis is chiropractic manipulation of the foot, ankle, knee and low back, soft tissue therapy (foot massage), semi rigid custom orthotics, and footwear recommendations. Physiotherapeutic modalities such as ultrsound are rarely necessary.
Definitely find a chiropractor that is familiar with extremity adjusting. If done correctly, it should work well. Take heed, though. Not all chiropractors are adept foot adjustors. It's not part of their core treatement. Also, if your foot wear is torturing your feet, all the treatment in the world won't help. Be certain that your shoes fit well, inlcuding length, width and stiffness.