Basically there are two different types of volleyballs, indoor and outdoor.  Leather is always preferred for indoor balls; however, you may want to choose a good synthetic if you are going to play outdoors near water.  There is not much difference between the top indoor volleyballs but when it comes to outdoor, Mikasa, Wilson and Spalding are a league above the rest. 

Before you Buy Indoor Volleyballs
There is not much difference in quality between the more pricey volleyballs.  Good balls are constructed with a layer of 18 leather panels around cloth layer around a rubber bladder.  Real leather allows the ball to age without much change in the play; however, some balls need to be broken in before they’re at their prime.  Synthetic leather just does not compare to the real thing.  Cloth-covered volleyballs are great for practice; offering the feel of leather while lasting much longer.

• Top Indoor Leather Volleyballs

Before you Buy Outdoor Volleyballs
• Top Outdoor Volleyballs