ACE is a good comprehensive program
(South Portland, ME)
I earned a personal training certification from ACE. Definitely go with one of the major certification companies as they are the ones that are well-respected and will get you hired. ACE is one of the top three.
You can take a study course with them if you want and if there is one available in your city, or you can study at home using
their materials or chance it (I wouldn't suggest that!). I did as much studying with their manual as I could (I had a baby at home and it was hard to get in enough studying), but I wish I had reviewed the outline for their exam better. Each company emphasizes different things on their exam, i.e. program design, anatomy, etc. so the ONE thing I would suggest is to really review their exam outline and study accordingly. I focused WAY too much on anatomy and not enough on program design, but I passed anyway. I can't say I wish I knew anything beforehand since I did a lot of looking in to what I needed to do to get certified.
About getting a better job, well, I could have gotten any number of jobs, but I chose to not work after getting certified because I wanted to focus on my kids. However, I can say that ACE has a great program where once you're certified, you're on their database and people can look you up and contact you. I got a job offer from someone doing that actually and I didn't have to do a thing.