For starters, if you check out Apple's website they tell you their requirements to become a licensed Apple reseller. To let you know, you have to do $100,000 in Net sales for 2 years before they will even look at your application. Good luck and hope this helps, but look for yourself their standards could have changed over the last year, but I doubt it.
Xbox 360 and PS3...there are several distributors who sell these but the margin isn't good. Many distributors can only knock about 10 bucks off of the MSRP. Good luck and if you find more places w/ better discounts let me know.