I liked In Pursuit of Excellence by Terry Orlick and The Grappling Game Plan by Lloyd Irvin. Got a lot of good information from those. Wrestle to Win! by Beasey Hendrix was ok too as it's grappling specific.
Lloyd Irvin's CDs were interesting but basically covered what's in the book. Just got sent some Paul McKenna Sports Performance audio files but not listened to them yet.
Although CDs and books can be useful the best psychological advice I usually get is directly from other people. Speak to your coach.