In order to become a pilot you need to gain a CPL (commercial pilots license) with IR (intrument rating). This can take as little as 14 months (or maybe less depending on weather) to achieve if you decide to go down the full time study route (AKA integrated course). The CPL/IR course contains ground school and flying training. Once you have your CPL/IR you need to get a job and gain 1500 hours of flying before you can get your ATPL (Air Transport Pilot License), which will be achieved as you fly with a commercial/cargo airline.
As with any job there are peaks and troughs, and aviation seems to change quicker than most. At the end of the day you just have to give it your best shot and rely on a bit of luck to land that first job. The type of person you are will affect how employable you are, along with the grades you can achieve while completing the course.
I am about to begin an Integrated course here in the UK (begins in May, CABAIR), so I am really looking forward to the challenges that are coming my way. Just to give you an idea of work involved, the course involves 800 hours in the classroom and 200 hours flying. There are alot of rules in aviation!
In terms of starting salary you will have to start at the bottom. A job in a cargo airline (turbo prop) can be around £25-30,000, moving onto jets 30-40,000. Once you become a Captain then you will start seeing much higher salaries, but don't be fooled you will have to work for it! I know that salaries over £100,000 are not unsual for pilots.
p.s. The above is correct for the UK, and I assume it is similar for the US.