I would highly recommend the work of Don Greene, who is a sports psychologist and performance coach. His specialty is working with individuals who perform under extreme pressure (e.g., Olympic athletes, Formula One drivers, pro golfers, SWAT teams, orchestral musicians). Now his work is primarily with musicians (at seminars, Julliard, New World Symphony in Miami, etc.). I've used his books and attended lectures and they are exceptionally good.
He synthesizes a number of techniques to allow one perform well under pressure. No psycho-babble or 'just relax' malarkey. He provides a very practical approach worth exploring.
Here's his site:
Links to his books:
1. Fight Your Fear and Win (for general public)
http://www.amazon.com/Fight-Your-Fear-W ... 172&sr=8-2
2. Performance Success (written for musicians, but outstanding for the 100 question self-assessment questionnaire)
http://www.amazon.com/Performance-Succe ... 172&sr=8-1
3. Audition Success (also for musicians, two case studies in interview form)
http://www.amazon.com/Audition-Success- ... 172&sr=8-3