Rbail,

We placed a graduate with Comair Airlines at the age of 52 last year.  To the airline it makes sense,  as they know they will have him for 8 years.  And, there are other opportunities available after 60, such as working for the airline's training department, or moving over to corporate flying.  

Now it's all a question of how long it will take for you to get the required certificates/ratings and experience (typically 1000 hours total flight time, and a FAA Commercial Certificate with Instrument & Multi-Engine Ratings) to qualify for employment with a airline. If you are starting from zero, it will take approximately 2 years before your are qualified, assuming you conduct training at a intensive flight academy.

Hope this answers your questions, feel free to write me privately if you have additional questions.

One suggestion I might offer up is to look at programs like the PACE program at San Juan College in New Mexico.  I am 51 and if I was going to do the airline thing and was just starting (with less than 500 hours) I would do that program.
 
You can have a job with MESA without doing the instructor job, with less than 300 hours, in like 1 year.  The faster you get the airline the faster you start making money and the more senority you get.