wanny
Striker
You don't need a personal trainer to find somebody to motivate you. I know that a lot of personal trainers don't have a f***ing clue. They do a simple course and get a certificate.
As a boxer I speak to bodybuilders for a bulk of my nutritional/conditioning advise, because they actually know what the fuck they're on about. I mean proper bodybuilders though, not fat bouncers.
Depends on who you are and what you do.
If you box, you will be training with others.
If you just do regular fitness training, you have far more chance of achieving your objectives and more importantly maintaining your schedule if you're using a trainer. It's easy to retain motivation to train by yourself over a month or two - over 6, 9 and 12 it's very difficult to keep going and keep improving. People who do train by themselves tend to at best maintain fitness.
You are right in that there's a lot of crap ones though, so very important to get a good one.
As mentioned on here before, I did BMF (British military fitness) classes for about three years (only stopped as moved overseas). They are essentially group training sessions, and while I've always been pretty fit they got me o a brilliant level of ll round fitness. Did a marathon off the back of them with little actual running training.