I don't know the closest place to receive CNA training, but I did want to let you know that I am a recruiter for the H. Lee Moffitt Cancer Center in Tampa, and we hire a ton of nursing students for various entry-level positions. The hospital is located on the USF campus, so for nursing students in the area, it is quite convenient. If you ever find yourself looking for a healthcare position in the area, let me know! If you want to check out the website, it is www.moffitt.org.
Best of luck!