Bruce, we just dug the mini pond 2 years ago with a new holland tc 45d. It is 3.5' deep in the middle and basically just a circle about 20' across. we put a few wheel barrow loads of pea gravel and picked up about 30 bigger stones from a field and lined the bottom. we have a small pump maybe like 5 gallons a minute from our big pond into the little pond. the extra water flows down a small water fall down about a 40' creek and back into the big pond. we planted wildflowers around the edges and took native shoreline vegetation from the big pond, as well as some lily pads and arrowhead from a neighbors pond.
It took 3 guys about 4 hours to complete the project. Our original idea was to raise fathead minnows for bait, etc, but I get fathead minnows for under $3 per pound and we realized it was much more fun to watch and feed gamefish than it was to watch and feed fatheads. We also have a nice population of crayfish that have thrived in the mini pond, we brought them in from the creek. Also if we shut the pump off, the pond will drain down most of the way in about 1 week.
Definitely is an awesome project that is very easy to do. I think the pump cost about $40, but the green light is what makes the pond AWESOME at night. It is pretty expensive though at $280, but very much worth every penny. I am going to try to get better pictures, next chance I get.