Body For Life is an integrated nutrition and exercise plan. There's tons of info about it in the Ladies Who Lift forum and lots of members like Frus who have done or are doing the plan and who'd be glad to help you out. I recall that there's some BFL discussion in this week's thread.
In a nutshell, the eating part focuses on six small meals per day, with a protein and carb serving at each meal. There isn't any weighing, measuring, or calorie counting (you use your palm and fist as a guide). The exercise component is three days of 20 minutes of HIIT cardio (High Intensity Interval Training) and three days of weight training, alternating upper body and lower body workouts. There's one Free Day per week when you don't work out and you can eat what you want.
It's entirely possible to do the plan without belonging to a gym if you have some basic equipment - like dumbbells - at home. You might want to borrow the book from your library to see if it would be a good fit for you.
Hope that helps!
PS - don't worry, lifting weights won't make you big and bulky - we women don't have the hormones for that. The more muscle you have, the faster your metabolism will be and the tighter and smaller you'll look.