Start fritzing and select breadboard view. You will then see a virtual copy of such a breadboard and can use it. To see examples, download a sketch (an fzz file) from the projects tab on the main fritzing page such as this one (chosen at random):
http://fritzing.org/projects/ejemplodemo
where you should download file inicio.fzz and then open it with fritzing. That will load a project that uses the breadboard for you to experiment with.
Peter
