Hello, I'm relatively new to the whole working out scene. I've made some attempts in the past with p90x and Insanity, but I couldn't get into them. However, in the last month I've found a schedule and a number of workouts that I've been able to stick with on a regular schedule. My goal is to trim off the fat from my stomach and build firm lean muscle. I have a goal to have a solid six pack by the end of the year, and preferably a nice physique elsewhere too. To clarify I'm not looking to bulk up like a body builder, I just want to look reasonably muscular.

My question to you all is what kind of calorie intake should I have if I want to both lose fat weight AND gain muscle simultaneously? I've done a BMR calculator that shows that between my current activity level and resting BMR I burn about 2700 calories per day. I would estimate that my average daily intake is about 1500-1600 on most days. I don't eat any fast food, drink any soda, I stay away from sugar (except coffee), and I try to avoid all junk food. Other than that, my diet isn't special, I just eat what the girlfriend cooks for dinner, usually something with chicken. I eat a sandwhich or something along those lines for lunch, and tend to skip breakfast because I work overnights. The reason I am confused is because everything I have read online says that I will lose fat weight if I burn more calaories than I eat (duh), but as far as GAINING muscle, I keep reading that I need to take in tons of calories, like 3.5k plus. Which would make me gain weight.. correct?

My workout routine is an hour a day of jogging, and 5 to 6 days a week of swimming 25-50 laps. I realize that I need to add some kind of weight training to this routine and probably an ab workout too. Any suggestions on that front?

Last question, are there any supplements that you all would recommend that actually work? As a biology/Chem major with a degree in nursing, I laugh at most of the products I read about with no science to back up their effectiveness. I considered anabolics, but I'm worried about the side effects. Plus I read that I would have to intake like 5k calories a day to make them work, which just is not going to happen.

For reference I am a 24 year old male, 5'10'', 155 lbs, and I don't know my body fat percentage.