Photoshop CS6 has a great blur control filter with the tilt shift blur.  There is also the lens blur and the field blur tool that gives creative blur control to images.  It can be over done and should not be used as a substitute for using the depth of field in camera to get the right zone of focus.  The image at the top is an example of using the tilt shift blur.  The other images are some photoshop edits from Craters of the Moon and winter fields in Idaho.