Are you looking for a shoe that has support for a low arch, or a shoe that has a low amount of arch support? You should sit down, extend your foot forward with no bend in the knee, and flex your foot without aide so that there is maximum arch present. I think that's what the doctor did with me when getting a mold for my inserts.
There was a company that i saw advertised in an issue of Tennis a few months ago. Does anyone know what the Web site was? I'm not happy with my insoles and got greatly ripped on them. They work for my body, but they are too short and I developed painful spots on my forefoot. Now I much cut out a portion of the original insoles of shoes to help extend the inserts I got. And they have developed small cracks in the heels and the material has ripped on one. Definitely try a self-moldable insert first, but not generic ones from some store. Been there, done that, I'd rather place squares of cardboard under the insoles. That place in Tennis looked to have a good insole; does anyone know the URL?