Once you go non-chemical, I don't have much advice. Lawns typically need N most of all (plus organic matter, especially with clay soil).
Other than grass clippings and coffee grounds, what relatively-concentrated organic sources of N are there?
Blood meal 12-1-0
fish meal or fish emulsion
guano
crab or shrimp waste
feather meal
Often, once you multiply the number of pounds in a bag of organic fertilizer by the "N number", (like 0.12 for 12-10-0 blood meal) and find out how few pounds of N you are getting, many organic fertilizers look very expensive compared to chemical fertilizers plus bagged compost or bagged manure.
