Any creek or pond that has areas of thick mud will have them in that area. I've eaten them and they tasted like a channel cat with a little extra fat on it. Just don't think it's worth the effort to clean them though, not very much meat for the size.
The yellow bullheads are the "best." I've caught them up to 3#, and they're not bad out of good water. I've caught black and brown bullheads from mossy ponds that the neighborhood alley cats turned their noses at.