Good source images are from high point, cities, mountains etc.. you get the point.
So i show you in a few easy steps how you get from this to..
Choose a suitable source image and crop the part you think sticks out.
Go into "Quick Mask Mode" by pressing Q.
Select the "Gradient Tool" by pressing G.
Select the "Reflected Gradient"
Draw a gradient in the region of the picture you want to be sharp.
Exit the "Quick Mask Mode" by pressing Q.
The area you want to blur out should now be masked.
Go to "Filter/Blur" and select "Lens Blur", play around with the settings to get a feel for it.
To get a good artificial look go to "Image/Adjustments" and select "Hue/Saturation" or use CMD+U. A value around 20-50 is usually good.
Hope you enjoyed my tutorial, if you have requests or questions feel free to post em in the comments.