At the moment, all I can recommend is a thorough reading of the current edition NEC in your area, and a copy of the NEC Handbook. I'll hunt around & see if I can find a "trade class" textbook in the next day or two.
I'll say welcome too. There are many good books out there on pool wiring. You just have to look for them, I know that Mike Holt has some, E.C.& M. had some books. Check with McGraw Hill too. What are you looking for?