One of my minor sins is to recommend things that I've yet to do myself. Shame on me. I really would like to try some of these recipies, but I'm just a little lazy. Here's some great sites where hobbyists share their homemade fish food recipies.
I feed my fish a "cocktail" of mysis shrimp, brine shrimp, phytoplankton, and cyclopeeze. It is worth mentioning that cyclopeeze is a godsend for the SPS reefers out there. The food comes in a frozen bar, and when defrosted it becomes fine food particles which are perfect for the SPS polyps to catch in the water column. It may no longer be necessary to target feed certain corals with the way cyclopeeze becomes evenly distributed in the water column.