Well not sure how organic your planning on going, but stuffs free so worth mentioning that Spent coffee grounds and Egg shells both can be dried out, crushed up, and used as a fertilizer.(Mainly Nitrogen, but they have some other trace elements.) Egg Shells also are a high %calcium carbonate which is what lime primarily is, meaning it can be a cheap replacement to buying lime but again I don't believe its as good.
Anyway just basically read as much as you possibly can, and then read some more, and you'll be thankful you spent that extra time when your done.