Hey - no need to post three times for one question!
A couple of places you can look for ball physics stuff:
http://forum.thegamecreators.com/?m=forum_view&t=35507&b=1 is a short tutorial on basic ball movement I wrote in response to a similar question,
http://forum.thegamecreators.com/?m=forum_view&t=37637&b=6 is a code snippet I wrote on projectiles, which gets a bit more involved.
These are pretty general concepts, but your question was very general. If you want more specific help then try to describe more precisely what you are aiming to do.