If you're doing baby led weaning, I found Baby Led Weaning by Gill Rapley to be really reassuring and confidence boosting.
But honestly, you really don't 'need' a book. Just feed them what you eat (whether whole or pureed if you're spoonfeeding) and avoid a few no-no foods like honey, whole nuts (nut butters are fine if you have no allergies in your family), and a few choking hazard foods, like peas, corn, raisins, if you are feeding whole (mashed or pureed is fine).