keeping track of calorie intake is fairly simple. Adding up how much you ate that day. Now, you can easily get your bmr and go from there, but this below should assist also. Roughly (roughly) tells you how much calories you be burning, given your body weight and duration of exercise.
http://primusweb.com/fitnesspartner/jumpsite/calculat.htm
http://primusweb.com/fitnesspartner/jumpsite/calculat.htm