Some circuit or systems software packages either don't have components with properties that can be loaded plus and play or that that don't provide for simple mock-up sketches. Researching today I came across the software called: Fritzing. It looks like it costs about $10 to download but seems capable of creating a several images, e.g. the proto-typing Arduino wiring images seen in many DIY forums. Interested to know if others have used this software or it there is another program similar to it out there?