Levling Strategy: Please define for me and answer questionsFollow

The book thing is FoV/GoV (Fields/Grounds of Valor) where you kill the specified mobs for exp rewards and some minor buffs. People don't really do it anywhere anymore. The level-down thing you mention is called 'level-sync', and it's used to level down party members so you can continue to exp off of lower level mobs. Now the normal thing to do is to use those books to solo your way to 30+ and either keep going, or try to get into an Abyssea party, which are rare themselves these days. All I can suggest is that you attempt to start your own. There are probably people wanting to exp on low level jobs somewhere, and you can probably do it with around 4-6 people and get decent exp.