If anyone is interested, the following link explains how to calculate projectile motion with air resistance.
http://wps.aw.com/wps/media/objects/...cs/topic01.pdf
I can't find the paper online that talks about effect of spin on the motion of a ball. It is basically calculating the Magnus force which creates lift for back spin and dive for top spin. You just add that force to the gravity force and the air resistance when you calculate the acceleration/deceleration. When I find it, I will send it to you. It is just an approximation since the minor details like dimples in a golf ball and stitches of a baseball can have a significant effect at high speed. However in FRC applications, the speed of objects and amount of spin that can be created is limited, and that approximation is qute valid in that range.