Thanks for the response. My issue is that manual selection of what is shown shouldn't occur, it all needs to happen magically.
Based on your comments and a few other things I've read, I started looking at it from the perspective of why display separate lists when I could join the related lists together into one view?
As a result I've started looking at something from http://msdn.microsoft.com/en-us/library/ff798514.aspx where you have an intermediatary list which links the values from list 1 to list 2. Now I'm struggling with a way to have this list displayed or data entered into it.