You don't have to buy a book for calorie counting, but Calorie King is a pretty handy way to always be able to look stuff up when you are on the go.
For me the key to calorie counting has always been logging what I eat. It keeps me accountable, and I'm a nerd for the reports.
I use FitDay, but there are other sites...everyone has their favorite site. I started with an excel spreadsheet...but a note book would work just as well. The point is to make a habit of it. Many people seem to be able to do it in their heads...but I dunno if it's that I'm bad at math or that I lie to myself....I have resigned myself to logging for the rest of my life. It really doesn't take that much time once you have your regular foods set up.
Maybe try logging without changing anything for a week...see how the WW points come out in calories.