I think I know how Red John knew the list before Jane...
It's quite a simple and obvious theory but think about it, maybe it's easier then we think.
So, here is the thing: Red John know that Jane is a mentalist (freaking smart).
OK, so he would assume that if Jane is doing a list he would check every aspect of each suspect, that include the time to do the killings and stuff.
So if Red John knows that Jane is really that smart and all, he would guess right the list if he just listed the people close to him, his connections, his ''friends'' or ''tools'' whatever you like, simply because he wouldn't underestimate Jane.
Well I think it's pretty much it, the only thing I could guess about this subject, what do you guys think?