Hi Steve.
I would say that you are looking at 12-18 months of full time equivelant study to do a good job. If you want to do the minimum to just barely pass the exams, you can possibly do so in 6-8 months. In any case, you will need a minimum of about 300 flight hours, and that's if YOU are really good.
With respect to your last question, you should get your private, instrument and commercial, then get any type of flying job. Part time is fine, as long as you get some type of paycheck. It may be necessary to get your CFI to get this job. Once you have this job, it makes your expenses for additional ratings deductible on your tax return.
Wherever you decide to train, make sure that they have a good simulator available. This will save you a great deal of money by flying lessons in the simulator first. The airplane is a terrible classroom. Unfortunately many of the flight instructors that you meet will just want to hop in the aircraft so that they can build flight time toward their next job.
Joe