I don't have to tell you that it is not cheap, but a lot of people do it. I paid for mine through the GI Bill. Did my four years and Uncle Sam helped me out.
Anyway, I wrote a blog entry:
So You Want to Be A Professional Pilot? It Will Cost You! - Almost the Speed of Sound which discusses the hight cost of flying and what you can expect to pay.
The numbers aren't hard numbers. I am sure it various greatly depending on where you do your flight training and how long it takes you will factor into the cost. Plus, consider "living expenses" when you are figuring it out.
Good luck!