There's a list of the interviews Peter covers here:
http://www.searchengineblog.com/interviews.htm
Read the Ralph Tegtmeier one and tell me you're not impressed:
http://www.searchengineblog.com/inte..._tegtmeier.htm
He makes more sense on the SE vs SEM relationship than anything I've read so far. Ad even though the interview is almost certainly a few years old, everything he covers is pretty relevant now as it was then.