Years ago, I was a personal trainer, so I can give you some advice.
Personal trainers are like any profession, there are very good ones and there are very bad ones. Even among the good ones, some are better at providing the type and level of service that you are looking for than others.
Before you start looking, jot down what you're expectations are. How much do you want to work out? When and where do you want to work out? What type of
exercises and activities do you like? What do you hate? Do you also want help with your
diet? The more you can ask your personal trainer, the better the match you will find. Some personal trainers will even tell you that you are not the right type of client for them, which is the level of honesty that you are looking for.
And if one thinks that you are asking too many questions, then run away. That is not the type of personal trainer you want.
Certifications vary, some are really good and some aren't. The two that are consider the best are ACE (
American Council On Exercise) and ASCM (
ACSM | ACSM Home). (I had the ACE certification.) A master's degree in exercise physiology is also good.
We've got a list of personal trainers on our site - You might find some in your area. We also have some online trainers listed as well. Keep in mind, that these a merely a point of information and I cannot vouch for the quality of them - so make sure you ask lots of questions.
By Region:
Personal Trainers, Gyms
Online:
Online personal trainers, online fitness programs 
