As for the deficit, around -600 a day will allow most people to lose 1 lb a week, while maintaining muscle mass. If you have more to lose, by all means run that deficit up to -1000 calories a day! That is what my coach did for his first round of P90X. He was 255lbs. and got ripped at 212 by the end of 90 days. That was obviously more than 1 lb. a week. It was all from running a daily 1000 calorie deficit. It takes commitment and determination, but sticking to a deficit pays off!
I have talked about the Fat Shredder percentages before: 50% protein, 30% carbohydrates, and 20% fats. These percentages maximize fat last. The high levels of protein keep you full and satisfied, and the lower carbs reduces the chance of any of those carbs will get stored as fat. I think it is beneficial to eat you carbs early in the day and make sure to eat some simple carbs (sugars from fruit for example) after your workout. That will replenish your glycogen stores. Beachbody's Results & Recovery is a perfect product for post workout. Use the P90X shopping list as a guide of what to eat. Then make sure your portions line up with your daily needs. Without going to far, here is a quick list of my common foods:
Chicken (white and dark - HAB free, local birds)
Turkey Lunch meat
Whey Isolate (just to supplement)
Pure Protein Chocolate Deluxe Bars (~$1 at Meijer)
Whole wheat bread (watch for HFCS)
Email me at firstname.lastname@example.org or FB message me! I want to help you get set up and on the right track. Keep bringing it!