Is this for a lawn, flower bed, or veggie garden? A lot of feed stores and independent nurseries carry it. Just keep in mind that it does inhibit seed germination, so it's not a good choice for gardens where you plan to direct sow. Dried molasses is another good option.

It's rather expensive for use as a fertilizer. Other seed meals will give you better bang for your buck, without the germination-inhibiting effects.

I use alfalfa pellets for organic nitrogen. $12 for 50 pounds at the feed store.

We've been using the Nature's Guide prepackaged stuff the past couple years now that it's being sold at several stores and nurseries in our area. Their "alfalfa based" Premium Turf Food has an N-P-K of 6-1-4 and looks pretty much like the feed store pellets The bags are a lot more expensive on a percentage basis than bulk, but only $10 to $20 more out of the annual yard budget for the small amount we use... a wash once the distance we now have to drive to a "real" feed store is factored in.

We also use their corn gluten meal on the lawn for a late winter pre-emergent/feeding combo, but go with the much less costly options at other times when there would be little weed control benefit. Calloways Nursery recently had the 40 lb bags priced right at $40. :-(

Here is a link that might be useful: Natures Guide product fact sheets