A quick word on sound effects. I found a fantastic online tool which allows you to create retro sounding effects. You can randomly create a sound then there are lots of tools to tweak the sounds to make it exactly how you want.
I created some sounds and saved them as WAV files. I found they were too quiet so I loaded them into Audacity and used the Amplify feature to make them all the same volume.
The link to ChipTone is here
