You have plenty of creek rock and a wagon to haul it in so dig a hole any shape sloping to about 2 1/2 ft deep then get some heavy black pond liner and lay it in the hole, start to fill some with water and smooth as you go then stack creek rock all the way around as your border. Makes sure you run an aerator in someplace as you set up. Lowes has pond treatments, I guess Walmart will too.