I suggest buying the book "Taking Charge of Your Fertility"!!!
I have used NFP for almost 10 years now. I also really like using an ovulation indicator/predictor tool. I use one called Lady Q. There are a lot of brands of these out there, First Response, ClearPlan Easy, Lunafert, The Donna, etc. Ebay sells a bunch, or you can do a web search. It's a good tool to use, IMO.
You'll also need some charts and a basil body thermometor (Walmart or Walgreens for cheap!)
I also have an extra NFP book (Cooperative Birth Control) if you want for $5 ppd (just pm me if you want it)
Good luck, it is the best choice for bc (IMO)!!