newbie questions

hey guys im; a newbie to this sight and also to my trans am, i just bought it 2 days ago. just a few questions i have. How do these axles hold up to the power, I was already thinking of getting a 12 bolt with 3.73,s, also how do the trannys hold up? How wode of a tire can i fit on the back. Which computer programmer seens to be the best(handheld). Also what headers will give me the most bang for the buck. well i'm sure i'll have somemore so i'll just there. o yeah how do u guys keep tires on these things i can't help but roasting them all the time.:drivin: