have you search craigslist? I usually find free listings on there.

here's one that seems good.

Here is a link that might be useful: free manure

thanks for the info grubby_me appreciate it

Just a word of caution about horse manure. If the horses have been grazing on bermuda pasture or have been fed bermuda hay you may be introducing these seeds into your garden. Even composting doesn't destroy all the seeds and we all know how hard it is to get rid of bermuda.