Flash manuals?? :bsmilie:
I have only one link which is very useful.
http://www.clubsnap.com/forums/forumdisplay.php?f=123
That's the place where they will share more about flashes or strobist. If you just want to know about TTL, in the flash manual do have explain how TTL works. For slaves too, depending on what model you are using.
Hope it helps you...
Cheers