Let me tell you, I gave up caffiene when pregnant with my first child, and I had awful, just awful, killer headaches for over a month, every day. It was one of the hardest things I've ever done, and that includes two babies born at home with no pain medicine!!
I honestly think the best way to get off of caffiene is cold turkey, just do it and get thru it and be done with it. I stayed away from it completely until after I had my 2nd baby, and then I started drinking a cup of green tea in the mornings. I had been so addicted to coffee that if I slept in I would wake up with a headache, so I really needed to get off of it. Now I will have a soda or a glass of iced tea, and I usually have my green tea in the mornings. I found that as long as I keep it in very low amounts, I can have a little without NEEDING to have that caffiene. I also found that my whole mood/energy/attention level is better when I have that small (30-40 mg as opposed to the 120 mg average in a cup of coffee) amount of caffiene.
It is definitely a drug and a very addictive one at that. I found for me that the only way to get rid of the addiction was to flat out quit, tho some people may respond better to a gradual weaning. I think either way you'll have to deal with the headaches, tho. I feel for you.