Hi Muck-Savage
Two sources I know of:
a) Pooleys do a book of pre-flight briefings with exellent visuals - they also do a PowerPoint CD-Rom to accompany it.
b) On-Track Aviation do a great manual which has the Pre-flight briefings in it as well as the detail of each exercise. These are probably more user-freindly if you are doing the FI course and want to put something simple up on the white board.
PM me, if you like, for more details.
Regards, ES