Top of the tree.  To become an Airline Transport Pilot, you will need to do a lot of flying, a lot of study, and be very healthy.  And quite rightly.  If you are at the sharp end of a 737, your passengers are going to want to know that you're going to take care of them.  

Most of the airlines offer some form of cadetship or training plan for their pilots, some will take on cadets and fully train them to standard, others will take in experienced commercial pilots and provide the additional training.  For details on which airlines offer what, it's best to go straight to their websites to find out, or give them a call.

Once you've made it, then you can start to earn the big bucks.

More info to follow.