Regardless of the style of pistol/revolver shooting you choose, be it bullseye, PPC. ICORE, IDPA, etc etc, you need to get the fundamentals down first.
You'll not find a better book the the Army Marksmanship Units, "Service Pistol Guide". It's put out by the CMP/AMU for $6.95. Don't let the price turn you off. It's the Mission of the CMP and AMU to instruct Civilians in Marksmanship. You'll not find a better reference by anyone at any price.
Study the book, once you get the fundamentals down, then you can move to the "action" style pistol shooting.
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