Could you by any chance beg, borrow or ermm, buy the book Learning Maya 6 Foundation? That has an excellent bouncing ball tutorial...

Looking at your animation you need to work on the timing first. Your ball starts to do some weird stuff when it gets to the wall. Next work on the bounce and set key frames where the ball strikes the ground, reaches it's zenith on each bounce and where it strikes the wall. Next up you could look at squash and stretch to give the ball some life when it hits the floor or wall (squash) and when it rises from the bounce (stretch).

Remember your ball will bounce lower with each bounce due to gravity and friction. Take a tennis ball or something like that and chuck at the wall outside and see what it does.

-Jacques