There are a bunch of modifiers available for controlling light. They range from a $15 umbrella to a $1000 Octabank. If you don’t have access to a store or studio where you can try out different softboxes and beauty dishes there are several websites that offer comparisons.
Here are a few links to websites that offer comparisons of different light modifiers.
and a little more light hearted comparison on blog Robbies Bubbles
Kansas City Photographer Steve Puppe